But as you stand in your backyard looking through that eerie orange or gray sky, you have to wonder: what about the garden? Your tomatoes, hostas, and apple trees are stuck outside breathing this stuff 24 hours a day.

Does wildfire smoke harm plants?

The internet is full of conflicting advice. Some bloggers claim smoke is great for gardens because it blocks harsh sunlight and provides carbon dioxide. Others warn that your vegetables are absorbing deadly toxins and should be thrown into the landfill.

The reality is that the smoke has both positive and negative effects. Let’s dig into the data and look at what wildfire smoke really does to plant physiology.

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What is Wildfire Smoke?

To understand how smoke affects a plant, we first need to look at what is actually inside it. Wildfire smoke is not just a single substance; it is a highly complex, dynamic chemical soup that changes as it travels.

It consists of two main components: gases and particulate matter (PM).

The Gases

When forests, brush, and unfortunately, homes burn, they release a massive array of gases. The most abundant is carbon dioxide (CO2), along with carbon monoxide (CO). However, the smoke also carries a mixture of volatile organic compounds (VOCs), nitrogen oxides (NOx), sulfur dioxide (SO2), and polycyclic aromatic hydrocarbons (PAHs).

As this gas mixture drifts downwind and interacts with sunlight, chemical reactions occur. This process creates ground-level ozone (O3), which is one of the most destructive components of smoke when it comes to plant health.

The Particulate Matter (PM)

The visible part of smoke consists of tiny unburnt bits of carbon, ash, and liquid droplets. Scientists categorize these particles by size:

• PM10: Coarse particles less than 10 micrometers in diameter (like dust or pollen).

• PM2.5: Fine particles less than 2.5 micrometers in diameter.

To give you some perspective, a human hair is about 70 micrometers wide. PM2.5 particles are so small they can stay suspended in the atmosphere for weeks and travel thousands of miles. It is these microscopic PM2.5 particles that do the most damage, both to human lungs and to the microscopic structures on plant leaves.

Effect on Photosynthesis

Plants rely on light, water, and carbon dioxide to make food through photosynthesis. Wildfire smoke strikes a direct blow to this process in two distinct ways: by altering light quality and by physically choking the leaves.

1. Diffuse Light vs. Shading

A thick blanket of smoke reduces the total amount of solar radiation reaching your garden. On heavily active smoke days, total light can drop by 10% to 50%. Less light generally means less energy for photosynthesis.

However, atmospheric science reveals an interesting twist. Smoke particles scatter light. Instead of direct, harsh sunbeams casting deep shadows, smoke creates highly diffuse light.

For a single, isolated leaf, less total light means less photosynthesis. But for a dense plant canopy—like a mature tomato patch or a fruit tree—diffuse light penetrates deeper into the lower layers of the plant. Leaves that are normally shaded by top growth suddenly get a uniform, soft light.

In commercial forestry and large-scale agriculture, studies show that light smoke can sometimes maintain or even slightly increase overall ecosystem productivity because the lower leaves work harder. But there is a tipping point. Once the smoke gets thick enough to block out the sun completely, the net benefit of diffuse light disappears, and total photosynthesis plummets.

2. Physical Blockage of Stomata

This is where the real trouble starts for gardeners. Plants breathe through microscopic pores on the undersides (and sometimes tops) of their leaves called stomata. These pores open to take in CO2 and release oxygen and water vapor.

Fine particulate matter (PM2.5) settles out of the smoke onto the surface of the leaves. Because these particles are often sticky with resins and oils from the burning vegetation, they don’t just blow away. They physically clog the stomata.

When stomata are blocked:

• The plant cannot efficiently absorb CO2.

• The plant cannot transpire (evaporate water), which is how it cools itself down on a hot day and gets nutrients from the roots.

• The mechanical abrasion of the sharp ash particles can tear the delicate waxy cuticle layer of the leaf, causing the plant to lose moisture rapidly and dehydrate.

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Effect of Increased CO2

Commercial greenhouse growers often artificially pump carbon dioxide into their facilities up to 1,000 parts per million (ppm) to accelerate plant growth. Since wildfires release massive amounts of CO2, shouldn’t this smoke act as a free fertilizer for our gardens?

In theory, yes. In practice, no.

While a localized boost in CO2 can technically increase the rate of photosynthesis, the plant can only utilize that extra carbon if it has ample sunlight and open stomata.

As we just established, wildfire smoke simultaneously blocks out the sun and chokes the stomata with ash. Such a plant cannot process extra CO2.

Furthermore, any minor benefit from elevated CO2 is completely wiped out by the toxic gases traveling right alongside it—specifically, ozone.

Effect of Ozone

While ozone high up in the stratosphere protects us from ultraviolet rays, ground-level ozone is a toxic air pollutant. It is formed when nitrogen oxides (NOx) and volatile organic compounds (VOCs) from wildfire smoke react in the presence of sunlight and heat. This means that even if the physical soot and ash have started to thin out, the invisible ozone levels downwind can remain dangerously high.

Ozone is arguably the most damaging component of wildfire smoke to plant tissue.

When a plant opens its stomata to breathe, it inhales ozone gas. Once inside the leaf, ozone reacts with the moisture in the plant cells to form reactive oxygen molecules that are highly destructive free radicals.

These chemicals attack and destroy the cell membranes, damaging the chlorophyll needed for photosynthesis. The visual symptoms of ozone damage on plants include:

• Stippling: Tiny, distinct dark dots or flecks (often purple, black, or bleached white) on the upper surface of older leaves.

• Chlorosis: Yellowing of the tissue.

• Interveinal chlorosis: yellowing of the tissue between the leaf veins.

• Necrosis: Dead, brown patches on the leaves.

• Premature leaf drop: The plant sheds its damaged leaves early to conserve resources.

Over time, chronic ozone exposure permanently weakens the plant, reducing its yields and making it far more susceptible to pests and fungal diseases later in the season.

Overall Change in Plant Growth Over a Season

How does this play out over a normal North American growing season? The physical and chemical stress of wildfire smoke results in a measurable reduction in overall plant growth and crop yields.

When smoke episodes last for weeks at a time during the peak of summer (June through August), plants enter a defensive survival mode. Because their photosynthetic engine is throttled by low light, clogged stomata, and ozone damage, they stop investing energy into new vegetative growth, flower production, and fruit development.

In agricultural studies across the midwestern and western United States, extended smoke cover during the summer has been linked to:

• Delayed ripening: Tomatoes, peppers, and winter squash take significantly longer to turn color and mature because they lack the sugars produced by active photosynthesis.

• Reduced fruit size: Fruit trees and fruiting vegetables produce smaller yields.

• Impaired flower pollination: High smoke density can physically deter pollinators like bees, and the reduced visibility alters their navigation systems, leading to poor fruit set.

For the home gardener, this means a temporary halt in your garden’s progress. Your plants will look stagnant, flowers may drop off without setting fruit, and the expected mid-summer harvest explosion will likely be delayed by several weeks.

Do Plants Producing Food Become Toxic?

This is the number one question I receive from concerned backyard growers. If my vegetable garden is covered in smoke containing toxic chemicals like polycyclic aromatic hydrocarbons (PAHs), heavy metals, and dioxins, is the food safe to eat? Or do the plants absorb these toxins, making the produce dangerous?

Let’s look at the science of how plants handle these compounds.

Do roots absorb smoke toxins from the soil?

Most of the heavy organic toxins found in wildfire smoke (like PAHs) are highly hydrophobic. This means they do not dissolve well in water and bind tightly to soil particles and organic matter. Because they are locked up in the soil complex, plant roots cannot easily absorb them. Even if trace amounts are taken up by the root system, plants lack the internal transport mechanisms to move these large, complex molecules up into the fruit.

Do leaves absorb smoke toxins?

The waxy cuticle layer on the outside of leaves and fruit acts as a highly effective barrier. While gases like ozone and CO2 pass through the stomata, the heavy, toxic compounds bound to particulate matter stay on the outside of the plant. They do not penetrate into the internal flesh of your tomatoes, apples, or zucchini.

The Real Risk: Surface Contamination

The danger is not internal absorption; it is external accumulation. The ash settling on your crops contains concentrated trace elements and particulates.

If you pick a tomato covered in wood ash and eat it directly from the vine, you are ingesting those smoke compounds.

The consensus from food safety authorities, including various university agricultural extensions, is clear: The food is safe to eat, provided it is washed thoroughly.

There is one exception: leafy greens. Crops with highly textured, crinkled surfaces like kale, lettuce, and Swiss chard can trap ash particles in their folds, making them very difficult to clean completely. If a smoke event was exceptionally severe or involved burning structures (which release much higher levels of synthetic toxins), it is wise to discard the outermost leaves of these crops.

What Can a Gardener Do to Protect Plants?

You can’t put a giant dome over your yard, but there are a few practical, science-based steps you can take to help your garden survive a heavy smoke event.

1. Keep the Soil Moist

When air quality is poor, plants are under extreme stress. Clogged stomata impair their ability to regulate water loss. Ensure your plants have steady, deep moisture at the root zone. Do not let the soil dry out completely, as drought stress combined with smoke stress can quickly kill a plant.

2. Avoid Overhead Watering (During the Smoke)

It is tempting to spray down your plants with a hose to wash the ash off while it’s smoky. Don’t do this. Wetting the leaves while ash is actively falling creates a sticky paste that cements the particles directly over the stomata, making the blockage worse. Wait until the smoke event has cleared before you wash the plants.

3. Wash the Plants After the Smoke Clears

Once the air clears and the wind changes, give your entire garden a thorough rinse with a garden hose. Spray both the tops and bottoms of the leaves to wash away the accumulated ash and crusty residues. This reopens the stomata and allows the plant to resume normal respiration and photosynthesis.

4. Put Away the Fertilizer

Do not fertilize your garden during or immediately after a heavy smoke event. Fertilizer encourages plants to push out tender new vegetative growth. A smoke-stressed plant needs to focus its limited energy reserves on cellular repair and basic survival, not on growing new leaves. Wait a week or two after the air clears before resuming your regular feeding schedule.

5. Delay Pruning

Avoid pruning or taking cuttings during a smoke episode. Every cut creates a wound that requires metabolic energy to heal and opens a pathway for opportunistic diseases at a time when the plant’s immune system is severely compromised.

Common Myths About Wildfire Smoke and Plants

Let’s wrap this up by busting some of the common myths circulating on gardening forums and social media.

Myth 1: “Smoke ash is a great fertilizer, so let it sit on the leaves.”

• The Reality: While completely combusted wood ash applied directly to the soil contains potassium and trace minerals, unburnt smoke residue sitting on the leaves is harmful. It blocks light, clogs stomata, and contains acidic compounds that can scorch leaf tissue. Wash it off.

Myth 2: “Plants cleanse the air of smoke, so my garden is helping the neighborhood.”

• The Reality: Houseplants can absorb minor amounts of certain VOCs inside a closed room, but a backyard garden cannot filter a moving mass of outdoor wildfire smoke. The volume of pollutants vastly overwhelms the plants’ capacity. The smoke harms the plants far more than the plants clean the smoke.

Myth 3: “Smoke causes long-term genetic damage to perennials.”

• The Reality: Unless a plant is physically scorched by fire, wildfire smoke does not alter its genetics. The damage is environmental and physiological. Once the air clears and new leaves grow next spring, the plant will carry no lasting “memory” or genetic defects from the previous summer’s smoke.

Myth 4: “You must throw away all vegetables grown during a smoke season.”

• The Reality: As discussed, toxins do not readily penetrate the interior flesh of fruits and vegetables. Wash your produce thoroughly with water (and a splash of vinegar if you like) to remove surface ash, and it is perfectly safe to consume.

Myth 5: “The Ash Changes Soil pH.”

• The Reality: Over thousands of years, the soil pH might change, but it won’t change in your lifetime. This myth probably stems from the fact that wood ash is alkaline, and when enough is added to acidic soil, it raises the pH. The smoke from forest fires is not adding enough ash to make a difference. The soil right in the burn area might see an increase in pH.

Are Forest Fires Getting Worse in Canada?

The news headlines clearly say yes. On June 11, 2026 the government said, “The 2026 wildfire season began more slowly than in 2023 or 2025, which were the worst and second-worst wildfire seasons in Canadian history.

That is not quite true. The following graph from the Canadian Government shows that the number of wildfires has been decreasing (green line) while the burned area has been higher in very recent years (blue bars).

Lightning causes about 46% of the fires, with many of the others being caused by human activity.

Climate change would cause increases in lightning strikes and more fires. That is not happening.

Burned area is based more on forest mismanagement and on how quickly resources are distributed to fight fires. It is not a sign of climate change or global warming. Forests in North America have been mismanaged for a long time.

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Traditional news outlets have lied about microplastics. I know it’s hard to believe!

New science is making the picture clearer.

It’s time to have a look at the REAL facts.

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What Are Microplastics?

Microplastics are tiny plastic particles measuring less than five millimeters across—about the size of a sesame seed or smaller.

They originate in two ways: primary microplastics are intentionally manufactured small (like microbeads in cosmetics), while secondary microplastics form when larger items like plastic bags, bottles, or synthetic clothing break apart over time due to sun exposure and weathering.

Because plastics do not biodegrade, these microscopic fragments persist indefinitely, but the particles do get smaller and smaller over time. They have contaminated our oceans, soils, and drinking water, and can easily enter the food chain. Science shows they are now found everywhere, from deep-sea environments to human tissues.

When you go to the store and buy a healthy green salad, it normally comes in a clear plastic clamshell container or a soft plastic bag. Both of these plastics shed microplastic particles onto your salad before you even get it home. When you eat the salad, you consume them and they accumulate in your body.

The False Narrative From Traditional News

An important study was released in 2021 called Estimation of the mass of microplastics ingested – A pivotal first step towards human health risk assessment.

It concluded that “humans may ingest 0.1–5 g of microplastics weekly through various exposure pathways”.

That range of 0.1 to 5 g is a huge range. One reason it is so large is that we did not have very good data to arrive at these numbers. So it makes sense for scientists to give a large range. They are in effect saying, we don’t know the number, but our best guess is a range of 0.1–5 g. There is nothing wrong with that - it’s good science.

Traditional news and online creators saw an opportunity for a sensational news article. They latched on to the “5g” value and ignored the fact that it was a wide range. Why be honest with the public?

It turns out that 5 g is about the weight of a credit card. So they came with headlines like this:

• World Economic Forum: “You eat a credit card’s worth of plastic a week, research says”

• CTV News: “You consume ‘a credit card a week’ of tiny plastic: study”

• WWF International: “Plastic ingestion by humans could equate to eating a credit card a week”

Let’s think about this. A credit card a week is 52 a year, or 520 over the last 10 years. Does this seem realistic? Can you imagine the amount of plastic from that many credit cards floating around your body?

Such headlines are not only misleading but also scare people for no good reason except to get clicks. They are also unfair to researchers. No researcher ever said, You eat a credit card’s worth of plastic a week. They were honest and gave their best guess using a range of values.

No wonder people have stopped trusting science. Science is routinely misquoted by the news.

Read The Fine Print

The 2021 study mentioned above also had this to say: “Despite the breadth of scientific literature currently available on microplastics, uniform methods for collection, characterization and analysis have not been employed. The lack of agreement on standardized approaches amongst the scientific community has resulted in an acute shortage of readily comparable data”.

Translation: The data we have is suspect. Even scientists can’t agree on how to measure microplastics.

This fine print never made it to the news articles!

I am not criticizing the science. In the early days of a scientific investigation, it is normal to have different researchers trying things and comparing notes. It is part of the scientific process that the general public does not understand. This is a good thing.

But it points to the fact that microplastic science is still in its infancy. We need to be careful how we use the information.

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New Data on Eating Credit Cards

A follow-up study looking at the methodology used to calculate the 0.1 - 5 g range found that even the 0.1g minimum was overestimated. This new study suggests that “a human eats a credit card's worth of microplastics every 23 thousand years”.

But …… even newer science suggests that even this number is an exaggeration of reality. Let’s have a look.

The Case Of Glove Contamination

A study released in 2026 shows that the nitrile and latex gloves used by scientists produce their own particles. These stearate salts can’t be differentiated from microplastics by most of the spectroscopy instruments used for testing. That means the current reported data for microplastic particles is much higher than it should be.

The gloves scientists use to prevent contamination are, in fact, contaminating the results and can cause overestimations of microplastics by 2000 false positives per mm².

It appears that this is only a problem when measuring smaller microplastic particles.

What does this mean? Some 72% of the reported data for microplastics prior to 2026 are not correct and overestimate the number of particles.

Microplastics in Blood

It is important to understand microplastics in the environment, but ultimately, what we really need to know is what happens to them in our bodies and in particular, in our blood.

Numerous studies of microplastics in blood, feces, urine, semen, placenta, arterial tissue, arterial plaque, thrombi, gallstone, tumors, bone marrow, testes and vitreous humor have been carried out using a technique called pyrolysis–gas chromatography–mass spectrometry (Py-GC-MS).

A recent 2025 study looked at the accuracy of this method to see if the previously reported values for the quantity of microplastics are valid.

The study authors noted that even for environmental monitoring, Py-GC-MS is in its infancy, and the technique is not fully understood. The method is an indirect analysis technique with numerous interfering compounds. It concluded that for blood, in particular, it is not an appropriate technique.

Conclusion: the most commonly used technique for measuring microplastics in human tissues, namely Py-GC-MS, DOES NOT WORK!

Do You Have Microplastics On the Brain?

In 2025, Nature Medicine published a study that reported our braqins contain 4917 ug/g microplastics. They also reported high levels in the liver, the kidneys, and placentas. All of these measurements used the Py-GC-MS method.

The scientists who evaluated the Py-GC-MS method, as well as other scientists, have pointed out that the method is flawed. The technique used can’t distinguish between microplastics and fat in tissues. The reported numbers are probably due to fat in the brain.

Bottom line: science does not know how many microplastic particles are in the brain.

Our Current Knowledge of Microplastics

Microplastics are real. Plastic products do break down into small particles over time, and we can find them in the environment, including the air, water, soil, and in our bodies.

We don’t yet know how big a problem this is. We also don’t know the number of such particles, but the number is certainly much smaller than any news reports you’ve seen.

Microplastics seem to be able to travel from soil into plants, but this information may need to be reevaluated given the above recent studies.

Microplastic science is still very new, and the reality is that we don’t know how harmful they are or even if they accumulate in our bodies. There is currently almost no evidence that they harm our health.

We do know that plastic does give off several chemicals that are of concern. These include bisphenol A (BPA), phthalates and PFAS (forever chemicals). There is clear evidence that these can potentially cause problems in our bodies. It is best to decrease your exposure to them.

BPA can also leach out of paper. For a discussion about the dangers of composting paper, see: Is it Safe to Compost Paper and Cardboard?

How to Protect Against Plastics

The internet is full of terrifying claims about microplastics, BPA, phthalates, and PFAS (”forever chemicals”). While you cannot eliminate them, science shows that a few simple, practical changes can drastically reduce your exposure.

Key Takeaways

• Heat is the enemy: Never heat plastic.

• Ditch the nonstick: Avoid PFAS-coated cookware.

• Dust regularly: Plastics accumulate in house dust.

In the Kitchen

The single biggest source of exposure comes from what we eat and drink.

• Stop Microwaving Plastic: Even if a container says “microwave-safe,” heating plastic releases microplastic particles and leaches chemicals like BPA into your food. Always transfer food to glass or ceramic before heating.

• Ditch Nonstick Cookware: Scratched or overheated PTFE (Teflon) pans shed PFAS directly into your meals. Switch to stainless steel or cast iron.

• Skip Bottled Water: Plastic bottles are a major source of microplastics. Drink filtered tap water from a stainless steel or glass bottle instead.

Around the House

Chemicals like phthalates are heavily used in artificial fragrances and consumer products. Look for “fragrance-free” personal care items to avoid them. Finally, since broken-down plastic fibers settle into indoor air, wet-dusting and using a vacuum with a HEPA filter will keep you from breathing them in.

Science is Great!

While you read this post, you might be thinking that it is a good example of why we should stop believing in science, but the exact opposite is true.

One of the greatest things about science is that it is self-correcting. In the early days of understanding a new topic, science does make mistakes. It is part of the process. It uses the best information and tools that it has. Experiments are done, and results are published.

Then other scientists replicate the work or try the experiments differently. They either confirm the initial results or cast doubt on them. This process continues until most scientists agree on a subject. We then believe the results until someone upsets our understanding with some new study.

That may seem like chaos, but it is an organized way of ensuring we reach the right answer.

The study of microplastics is in its infancy. We are just starting along the journey to understand them. Stay tuned; more surprises are on their way. We just don’t know when or what they will be. And Reality Time will be here ready to report on the discoveries - so make sure you subscribe.

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I looked into the details and found that CBC, along with other traditional news outlets, never checked the company’s claims. Why would they? It might destroy a sensational headline-making story!

Further investigation revealed a company that was making claims about its product that were poorly supported by science.

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Development of a New Tick Repellent

Two boys in Nova Scotia, Canada, developed Lyme disease from tick bites. Unwilling to use conventional preventative methods such as DEET because they were “chemicals”, their mother, Lisa Learning, started testing home remedies to prevent this from happening to others.

The result of this work was the creation of a company called AtlanTick, which started selling a product called AtlanTick Outdoor Spray. “A few months later, she forged a partnership with Acadia University to delve deeper into the world of ticks and discover an effective, scientifically validated, natural solution” (quote from the current website).

Note that the product went to market prior to being tested by scientists to validate the efficacy of the product.

The company and product have now been rebranded to PureGard and PureGard Botanical Repellent Spray.

The main ingredient in the product is PMD (p-menthane-3,8-diol), derived from Oil of Lemon Eucalyptus (OLE).

The Claims by PureGard

Claim #1: “The CDC recognizes PMD as the only plant-based active ingredient comparable to DEET, providing long-lasting protection against mosquitoes and ticks.”

The Facts: The CDC says the following about controlling ticks: “Treat clothing and gear with products containing 0.5% permethrin.” AtlanTick was originally promoted as a clothing treatment option, but the CDC does not endorse OLE or PMD for this purpose.

The CDC does say, “Use Environmental Protection Agency (EPA)-registered insect repellents containing DEET, picaridin, IR3535, Oil of Lemon Eucalyptus (OLE), para-menthane-diol (PMD), or 2-undecanone. Always follow product instructions. Do not use products containing OLE or PMD on children under 3 years old. When used as directed, EPA-registered insect repellents are proven safe and effective, even for pregnant and breastfeeding women.”

Note that 2-undecanone is also made from plant extracts, so the claim “CDC recognizes PMD as the only plant-based active ingredient comparable to DEET” is incorrect.

Claim #2: “The Peer-Reviewed Proof: PMD Outperforms DEET Against Ticks”

The link provided on the company’s website does not go to a peer-reviewed research study. Instead, it goes to a review of other studies. It does state, “PMD exhibited better protection against ticks than DEET, by inhibiting attachment and blood-feeding of tick vectors”. Unfortunately, the reference provided to support this statement does not lead to a study of PMD. Instead, it goes to another review, which states in the abstract that “Descriptive analysis of the data sources identified the most effective application of insect repellents as a combination of topical chemical repellents, either DEET or picaridin, and permethrin-impregnated or other pyrethroid-impregnated clothing over topically treated skin.

It does go on to say, “Topical insect repellents containing IR3535, picaridin, or oil of lemon eucalyptus (p-menthane-3, 8-diol or PMD) would offer better topical protection than topical DEET alone”.

The reference provided does not list an actual study that looked at how well PMD repels ticks.

Claim #3: PureGard, on their “Research” page, says the following: “The 100% Efficacy Field Study: Independent global testing proved that a topical application of Oil of Lemon Eucalyptus (PMD) achieved 100% complete protection for 6 to 7 hours in real-world tropical field conditions”.

Clicking on the link takes you to a review with the title: Plant-based insect repellents: a review of their efficacy, development and testing. It is not a field study- it is a review report. The report’s summary says, “To date, insufficient studies have followed standard WHO Pesticide Evaluation Scheme guidelines for repellent testing.”

Note: this review does not mention ticks except in the references. It is almost entirely about mosquitoes. It does not say PMD is effective for ticks. Nor does it mention “Independent global testing”.

The claim by Puregard uses the term. “Oil of Lemon Eucalyptus (PMD)”. But oil of lemon eucalyptus and PMD are different compounds.

The reference used by PureGard does not support claim #3.

Claim #4: In its Q&A section, it says, “ Our products were tested with Acadia University and results were published in peer-reviewed journals”.

1. There is a study that used an early version of the AtlanTick product, but there is no study that looked at the PureGard product.

2. The study did not do field testing of the product (see below).

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Is PMD Safe?

Proponents of PMD make the point that it is a “natural extract of oil of lemon eucalyptus” and imply that since it is “natural,” it is safer than the man-made toxic DEET!

The EPA classifies DEET as a category III, slightly toxic compound. PMD is classified as a category I, highly toxic compound. DEET is a safer option, although the dose in a product is important.

Stop being fooled by “natural” claims for products.

Studies on the Effect of PMD on Ticks

I did find studies that looked at PMD as a tick repellent.

One study found PMD was toxic to ticks, but this was a lab study that never compared its dose levels to the dose levels of realistic products.

A second study concluded, “that menthane-diol stereoisomers (PMD) has potent repellency activity against the Brown Ear tick and can be used in the management of ticks and insects in livestock.”

I found no field studies that looked at the tick repellency of PMD or a commercial product containing PMD. This is important. One thing we have learned by looking at mosquito repellent studies is that lab studies can not be extrapolated into the field. When the University of Guelph looked at mosquito repellents, they found that products which worked in labs tended to fail in real-life field studies.

Research By Acadia University

Dr. Nicoletta Faraone, an associate professor in Acadia University’s chemistry department, led a research project that looked at the effect of PMD on ticks. She found that PMD did repel ticks in lab studies.

Dr. Faranone goes on to say, “Ticks exposed to PMD are less likely to crawl on you, and even if they’re brave enough to do so, they’re far less likely to bite.” She also cautioned, ”Before you run out and start drenching everyone in the natural oil, these were controlled lab studies, and the results may not be replicable out in the woods.” Entomology today has a good review of this research.

In this study, Dr. Faraone also tested an early version of the AtlanTick product, which was found to be effective at repelling ticks. The study did not test a PureGard product.

What Are Field Studies and Why Are They Important?

A field study is a research project conducted in a real-world setting. In the case of ticks, it would take place outside with real people walking through grass or wooded areas to see if various repellents reduced the number of tick attacks.

Without such studies, we do not have scientific evidence that a product works. Just because ticks do not move towards PMD in a lab setup does not mean it prevents tick attacks when you walk through a natural setting.

The necessity for field studies has been proven many times in science. For example, numerous products, such as fragrant plants, seem to be effective against mosquitoes in a lab, but when tested outdoors, they fail to work.

It is also important to test real products. A lab-extracted PMD can be quite different from the oil of lemon eucalyptus in a product. Citronella candles are a good example. In a lab, citronella oil repels mosquitoes, but citronella candles don’t work.

Another reason such studies are important is because of tick behaviour. Unlike mosquitoes that fly around sniffing the air to find a target that they like, ticks are blind and sit in wait to “jump” on their prey. For fragrant chemicals to work, they need to be strong enough to prevent such action. The tick needs to be able to smell you coming and have enough time to decide not to jump.

I found no field studies for PMD.

Do Field Studies Exist for PMD?

PureGard claims they exist on their website when they say “The 100% Efficacy Field Study: Independent global testing proved that a topical application of Oil of Lemon Eucalyptus (PMD) achieved 100% complete protection”.

But I could not find any, so I asked PureGard for a copy of the study.

They confirmed by email that they don’t have such a study! They suggested I contact Dr. Faraone for it, and I did just that. To date, she has not provided one.

As of today, there is no field study for either PMD or the PureGard product to show a reduction of tick attacks on humans.

The Bottom Line

It is possible that PMD will reduce the number of tick attacks on humans, and products containing the chemical may also work. In order to verify that a product works, research needs to do field testing on it.

I have no reason to think the PureGard product does not work, but I also have no scientific support to show that it does work. Until such a study is done, we should be very cautious about making claims for a product.

This is a big problem in many industries, including herbal medicine, organic garden products, and natural health products. Manufacturers are allowed to make just about any claim about their product.

Buyers need to start asking for scientific proof of such claims.

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Such seeds are normally planted as soon as the soil can be worked. It is usually still cold and can even get snow and frost. The seeds of cool-season crops don’t seem to have a problem dealing with these harsh conditions.

I’ve been gardening for 50 years and have given classes on vegetable gardening and made many videos on the topic. I have always told people to plant their cool-season seed as soon as they can. That is the advice everyone gives.

But ….. we may have been doing it wrong!

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The Old Science is New

I was looking through some seed starting information and came across a list of vegetables and the best temperatures for germinating seed. I noticed almost all vegetables germinated best at about 85°C.

I checked out some cool-season crops like peas and lettuce. The temperature they preferred was about the same as warm-season crops like tomatoes.

That made no sense at all based on common gardening advice.

Why are we planting pea seeds in cold weather when they prefer a warm temperature for germination?

My first step was to check this data to see if it was right. Several US Extension offices report the same data. In fact, it was identical data, so they are clearly repeating it.

I tried to track down the original study, with some success. I never found the original scientific paper online; however, the tables I did find were created by a JF Harrington who has published numerous papers on starting seeds. I even found his thesis, called Drying, Storage, and Packaging Seed to Maintain Germination and Vigor.

I feel confident in accepting the germination/temperature data as published.

The following table shows the time required (in days) for germination at various temperatures. Testing was done in soil and based on seeing a shoot above the soil line. The fastest germination in almost all cases was at 86°F (30°C).

Why Do We Plant Seeds in Cold Soil?

The data shows us that planting seeds in cold soil is a bad idea. They take far too long to germinate - so why do it?

Our advice to plant in cold soil is based on the plant’s need to grow in cool weather. Many of these cool-season crops need to finish growth by early to mid-summer, because they can’t take the heat.

But they also germinate better in warm conditions.

Rather than plant cold and grow cool we should be germinating warm and growing cool. But how do we do that?

One solution is to germinate indoors and plant out seedlings, but that is a whole lot more work, requires more space and equipment. Another option is to germinate warm and plant seeds that are just starting to germinate. This is easy to do with my baggy method.

Start seeds with the baggy method, in a warm room, and plant out the seeds once they germinate. It is a bit more work, and it is a bit harder planting wet seeds, but if you are only planting a small number, it is quite easy.

The benefit of this new method is that you get seedlings growing much more quickly, as you’ll see in my test below.

Testing: Germinate Warm, Grow Cool

I decided to run an experiment to test two things.

1. Is the data in the above table correct? Does cool-season seed really germinate so much slower in cold conditions?

2. Will warm germination speed up early plant growth?

I took 40 pea and 40 beet seeds and split them into two groups. Group C (cold) was germinated cold, and group W (warm) was germinated warm.

Both groups were put into baggies for germination, following my standard method (see above video). Group W was kept at room temperature, and group C was put in the fridge to mimic cold soil (7°C/45°F).

They were started in early May in zone 5. This year we had a very cold, cloudy May, so everything was behind in the garden.

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Seed Germination

Group W peas germinated in about 2 days. You can easily see the radicle develop under the seed coat. The beets took 3-4 days. They were then planted in a container outside.

Group C peas took almost 3 weeks to germinate, and even after three weeks, the Group C beets were still not germinating.

Growing Seedlings

By May 31, Group C would not be showing above the soil level.

Group W sprouted a couple of weeks earlier and are now good-sized seedlings.

Is The Data in The Table Correct?

My fridge was 7°C (45°F). Based on this temperature and the data in the table, peas should germinate somewhere between 13 and 36 days (this is not a linear range). Beets should germinate somewhere between 17 and 42 days.

Keep in mind that since the data in the table depended on a shoot showing above the soil line, its “days to germination” are a bit longer than the real germination time you get by looking at seeds in a baggy.

My germination times were in the ballpark of these numbers. There was definitely a big difference in germination time between the fridge and room temperature. Based on my results, I have no reason to doubt the data in the table, which I am sure are more accurate than my numbers.

A Better Way to Grow Cool Season Crops

This is not a very rigorous experiment and should be redone with more types of seed, but both the germination data we have and this little demonstration convince me that we should be growing our cool-season crops differently.

Germinate warm using the baggy method. Once germination occurs, plant outside.

This new method will get plants growing a couple of weeks earlier, giving them a longer growth period early in the season when temperatures are still cool.

Does this produce a larger crop? We don’t know that from the data presented, but since gardeners jump through hoops to get an early start for these crops, I would be surprised if it didn’t improve yield. This is especially true with leafy greens and peas that just can’t take the heat. Things like beets and carrots are not as heat sensitive.

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Become fascinated with fasciation.

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What is Fasciation?

Fasciation is also known as cresting, and African violet (AV) enthusiasts call it zippering. It is a relatively rare condition in which the growing tip (apical meristem) develops abnormally. This growth produces flattened, ribbon-like stems with a fan-like enlargement on the end. In flowers, it produces flattened, wide flowers with an unusually high number of petals.

The actual shape that is formed depends on the location of the meristem and the species of plant demonstrating the phenomenon.

In stems, it causes flattened stems which may also have weird curved shapes.

The cause of fasciation is not well understood and can be caused in several ways:

• Hormonal imbalances

• Random somatic mutations

• Bacterial and viral infections

• Fungi, mite or insect attack

• Exposure to cold

• Genetic inheritance (eg cockscomb Celosia)

“In some plants a single recessive gene controls this condition, although the degree of expression is often very dependent on environmental conditions”.

Fasciation affects the appearance of a plant but does not affect the health of the plant, nor its cultural requirements.

The last cause on the list is of particular interest to plant enthusiasts. Fasciated specimens of cactus and other succulents with their unusual forms – which can often be perpetuated by vegetative propagation and are highly sought by collectors. Many of the ones perpetuated by vegetative propagation become cultivars with descriptive names such as ‘Monstrosa’, ‘Cristata’ or ‘Tortulosa’.

The condition is rarely passed on through seeds, but an exception is that the “cockscomb” cultivars of celosia (Celosia argentea var. cristata) are grown especially for their dependably fasciated flower heads.

Fasciation in African Violets (AV)

African violets, along with streptocarpus, belong to the gesneriad family, but they seem to demonstrate a different form of fasciation than found in streptocarpus (see below).

Most of the fasciation reported in AV is in the form of modified leaves. The petiole of the leaf may be wider than usual. The leaf may have two parts to it, a condition referred to as “zippered”. In some cases, the left half of a leaf has a slightly different shape than the right side of the same leaf.

If the above leaf is used for propagation, they generally revert to normal leaves. It is not a one-time unstable mutation.

Fasciation can also affect the crown of the plant. In this case, you get a wide crown instead of a normal circular one. In the following picture, you see a wide crown going from the top of the picture to the bottom.

Growers report that plants growing this kind of crown won’t flower, and if leaf propagated, the resulting plants will also form a “zippered” (fasciated) crown. It is a permanent mutation, and you might as well discard the plant.

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Fasciation in Other Gesneriads

I found only one example of fasciation in a gesneriad other than AV or Streptocarpus, and that is a flower tip on this Sinningia eumorpha.

If you have pictures of other examples, please let me know in the comments.

Fasciation in Streptocarpus

The occurrence of fasciation in streptocarpus seems to be rare, or at least it is rarely reported. I became interested in the phenomenon because several of my plants have demonstrated the condition, and in some it even seems like a stable mutation.

It can affect the flower stems, forming flat stems that then produce numerous flower buds at their tips. These usually open to form normally shaped flowers. However, in some cases, one or more of the flowers becomes a double flower with 10 petals.

Part of the purpose of this post is to document these examples and to carry out some tests to better understand the condition.

A number of my plants form fasciated stems. Once a leaf forms such a stem, all following flower stems on the same leaf also tend to be fasciated.

The flowers on such stems are usually normal, but such stems can also form double flowers. Normal stems do not form double flowers.

I have found very little information about the cause of fasciation in streptocarpus and no research studies on it. Some interesting questions remain:

Stability of the Mutation: How stable is the mutation? Streptocarpus flower stems are formed on a leaf, not from the crown of the plant. Once a leaf forms a fasciated stem, each subsequent stem is also fasciated. Do leaf cuttings transfer the trait?

Effect of Environment: How does the environment (light, temperature, fertilizer) affect fasciation? Double flowers?

Cause of Double Flowers: What causes the double flowers? They are not consistently formed on a fasciated stem. Is it just a matter of chance, or does the environment affect the flower's form?

I have set up some experiments to try and answer these questions and will post results as they become available.

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Canada committed genocide! Canadians started feeling guilty. Then the government gave indigenous groups huge sums of money to compensate for these past crimes. It all seemed like a horror movie.

But ….. and there is a huge BUT ….. the story is mostly fiction. The Canadian citizens did pay out large sums of money, but not because we committed genocide. There are no unmarked graves. Very few children were “sent” to residential schools; most wanted to go or at least their parents wanted them to go. Some children did die at the schools, but the number of deaths was fewer than if they had stayed home.

It is time Canadians and the rest of the world know the truth.

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A Grave Error - A Must Read

Much of the information in this post comes from the book Grave Error. I will summarize some key points, but there is much more to learn in the book.

Purchase Grave Error from Amazon.com

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Unmarked Graves at Indigenous Schools

Several indigenous groups used ground-penetrating radar to search for unmarked graves. They did find anomalies and then went on to claim that the schools had murdered children and buried them without any record.

I have reviewed this in depth in Indigenous Grave Sites and GPR.

The reality is that NO unmarked graves have been found. There were no mass murders. There are no missing residential school children.

Unfortunately:

1. Indigenous groups keep pushing this false narrative.

2. Justin Trudeau, prime minister at the time, along with some of his ministers, misled the whole country and paid out large sums of money instead of checking the facts.

The Truth and Reconciliation Commission (TRC) concluded in 2015 that there was no reliable evidence of a single homicide committed against any students by any staff throughout the entire history of the Indigenous Residential Schools.

The Myth of Forced Attendance

In a speech to the United Nations in 2010, Murray Sinclair, who was then Chair of the Truth and Reconciliation Commission, declared: “For roughly seven generations, nearly every Indigenous child in Canada was sent to a residential school. They were taken from their families, tribes, and communities, and forced to live in those institutions of assimilation”. (Chapter 15 of Grave Error).

In an article by Indigenous Foundations, Erin Hanson claims, “In 1920, under the Indian Act, it became mandatory for every Indigenous child to attend a residential school and illegal for them to attend any other educational institution.”

Mainstream media parroted these ideas and reported that indigenous children were forced to attend the residential schools.

All of these claims are false!

Here is just one example showing how ridiculous these claims are. Several bands wanted IRS and even contributed to their building costs. In the 1940s and 1950s, the government started closing residential schools, and many tribes and parents requested that they stay open. The indigenous community at that time understood the value of the schools.

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Were Children Forced to Attend Residential Schools?

This is a false narrative. Children from normal, stable homes who had responsible parents were never forced to attend residential schools. In fact, parents had to make special written requests to have their children attend such schools, and many parents did just that, believing their children would get a better education. For most students, it was a choice.

Children living in abusive homes, or orphans with no homes, might have been sent to the schools because they were used as a form of orphanage for children with no other place to go. Leaders of indigenous groups normally sanctioned such attendance and were certainly involved in the decision.

The term indigenous includes Metis, and they were discouraged from attending the IRS, further confirming that not all indigenous children attended these schools.

It is estimated that only 1/3 of the indigenous children attended IRS, not the nearly 100% Sinclair claimed.

The residential school program was initiated in 1883 in response to the desperate condition of Plains Indians. Game and buffalo had become sparse. The Canadian government helped out with rations and other financial assistance. The indigenous groups were not able to provide proper education, and so partnerships were arranged with churches to provide children with an education. These were set up with the complete approval and endorsement of the indigenous people.

Education for all children was not mandatory until 1916 in Saskatchewan and Alberta, and 1917 in Manitoba. The requirement for indigenous children on reserves was to attend the nearest available school, which could be on a reservation. There was never a requirement to attend a residential school.

Even after education for children became mandatory, many indigenous children did not attend a school.

The Myth of Cultural Genocide

The National Center for Truth and Reconciliation posted this on their website: “Residential schools were a systematic, government- sponsored attempt to destroy Aboriginal cultures and languages and to assimilate Aboriginal peoples so that they no longer existed as distinct peoples”. The TRC characterized this intent as cultural genocide.

This is a lie!

The schools were designed to provide an educated indian class who could become leaders in either Canadian or indigenous societies. Their goal was to provide an education system that was not available in indigenous communities. The church was interested in developing future educated priests, nuns, and ministers.

Many of the indigenous families were catholic and wanted their children to be educated in a catholic-based school system.

It is regularly claimed that the schools forced children to speak English in an effort to abolish native languages. English was the most common language used in Western Canada, as well as the language used by teachers in the schools. It should come as no surprise that English was the preferred language at the schools.

Indigenous children learned their traditional language and customs at home before they became old enough to attend school. They were also free to attend schools on reservations that taught their own language and culture. Once they graduated, they were free to return to their community and continue with their customs.

The average length of stay at an IRS was 4.5 years, and those with homes went home for the summer and even on weekends where possible.

How powerful were the schools? Children start learning things at home at age 4, and at school until possibly age 16 (oldest kids in the IRS). That is 12 years of learning. But only 30% of indigenous children did their learning at IRS, and for those that did, they only spent an average of 4.5 years at the IRS, which is more like 4 years once you take into account summer holidays and weekends.

That means, on average, indigenous students spent 10% of their educational years at a residential school. The other 90% of the time was spent in their traditional home being educated through traditional means. Is it realistic to blame the residential schools for eliminating language and culture when students only spent 10% of their time at these schools?

That is a ridiculous claim! Teachers were good - but not that good.

There was no attempt to squash their native language or culture. Efforts were made to educate the children in a Canadian way of life so that they would be better able to be part of the Canadian society.

If the IRS were committing cultural genocide, why were indigenous people completely unaware of the situation?

• Various indigenous groups asked the Canadian government to build and run an IRS near their communities so that their children could get an education.

• After 1980, many schools remained open but were run by Indian bands. Were they also committing cultural genocide?

• When Cross Lake’s residential school burned down, the band asked for it to be rebuilt. Would they do that if they thought it was destroying their way of life?

Some schools did have uniforms, much like modern catholic schools. But other schools allowed students to dress in a variety of clothes. Some see this as a removal of indigenous customs, but in reality, it made it much easier to manage the schools. It was also a way to provide proper clothing to children who arrived at school without it.

It is also important to realize that Nations quickly adopted the culture of Europeans. They used their clothing, weapons, and shelters. It is a natural progression for a society to adopt things that make life better. But now, some indigenous groups are calling this cultural genocide.

Residential schools did not ban indigenous traditions and did not forbid indigenous children from speaking their languages. On the contrary, the government of Canada published dictionaries of indigenous languages to help teachers and students.

By the time residential schools were started, almost none of the student homes were practicing their traditional culture. It had already become a mix of indigenous and European culture, and that continued to change up to the current day. It could, therefore, be argued that indigenous peoples caused their own cultural genocide.

The reality is that English, and to a lesser extent French, was a major requirement to function in the rest of Canada. Schools would have been remiss not to teach it. Learning English was also a key reason why parents sent their children to residential schools.

The TRC makes claims of cultural genocide and even defines it as “the destruction of those structures and practices that allow a group to continue as a group”. However, in its 3,500 pages, it does not provide a single piece of evidence to support the claim.

The Lost Children

In 1990, in an interview with Barbara Frum of CBC, Phil Fontaine, then Manitoba Region Chief of the Assembly of First Nations, made allegations of sexual abuse at IRS by other children.

This was followed by numerous stories of murders and clandestine burials. It was claimed that many indigenous children at IRS were never returned to their homes, never to be seen again.

• There is no record of a single student being murdered by teachers or administrators of the schools.

• There are no records of indigenous parents claiming that their children were missing.

• The TRC interviewed hundreds of parents and did not document a single case of missing children.

It is interesting and very telling that this type of claim was not made before the 1990 interview. And yet, suddenly, all kinds of people remembered that these events took place.

It is important to note that not all indigenous people make such claims. The book, Grave Error, documents numerous indigenous leaders and authors who categorize the claims as false.

I find it hard to believe that hundreds of students went missing, and none of the parents did anything about it. I understand why some would not report the problem to Canadian authorities, but surely they would report the problem to band chiefs. And they, in turn, would have made some report of the instance? At the very least, this would include a letter to a newspaper or a government office. But no such evidence exists.

All we have are stories with no evidence of missing children.

The Truth and Reconciliation Commission Fails

I distinctly remember the announcement that the Truth and Reconciliation Commission was being formed and tasked with finding the truth about how indigenous peoples were treated. It sounded like a great idea.

The staff of the commission would gather evidence and determine the truth - or at least that is what the title of the commission suggests.

On the day of the announcement, indigenous leaders and members of the commission made it clear that the process was in trouble. They clearly stated their goal. It was to travel across Canada and give everyone a chance to “tell their story”. There was no mention of actually gathering evidence or determining the facts. What was much more important was to hear “stories”.

What should the commission have done? Examine police and band reports of problems. Examine reports in government files. Interview everyone involved in those reports to determine the real facts surrounding any claims. How else can you determine the truth?

None of that mattered. It was more important to listen to stories with no evidence supporting the claims.

The validity of the claims in the TRC Report and the methodology used to gather information have been extensively reviewed by authors Rodney Clifton (worked at a residential hostel in Inuvik) and Mark DeWolf (IRS student), who wrote From Truth Comes Reconciliation. Everyone should read this book, but I will summarize some of its key findings below.

Purchase From Truth Comes Reconciliation from Amazon.com

Purchase From Truth Comes Reconciliation from Amazon.ca

The TRC made numerous errors in reporting on the facts surrounding the IRS, some of which have been documented above.

The report did a good job recording people's negative memories of residential schools, but it failed to verify any of the claims. There were no cross-examinations, and witnesses could report their story in private. The reports are very one-sided and do not reflect the real history. Brian Giesbrecht, a former Manitoba courts judge, concluded that the accounts “showed a lack of concern with the truthfulness of the evidence”.

The conclusion of the report, the section most people read, is extremely negative and does not reflect the evidence that was collected and documented in the main body of the report. Positive reports about the IRS were universally ignored.

The TRC makes claims of physical genocide, defined as the mass killing of members of a targeted group. But the report provides no evidence to support this claim.

The TRC makes claims of cultural genocide, but as demonstrated above, there is no evidence for it. In fact, some of the testimony in the report clearly contradicts such a claim.

At the beginning of the process, the commission clearly said it wanted to hear from school staff and other non-native students. The oral records collected were overwhelmingly from indigenous people who identified as " survivors”. A professional historian on the TRC staff said that the commission’s actions “were not consistent with its claims to include non-Aboriginal voices. The budget for interviewing school staff was cut from $100,000 to just $10,000. Compare that to the total expenditure of $60 million, and you get a good idea of how unbalanced the interviews were.

IRS started to close in the 1950s, and few remained by the 1980s. Only 30% of indigenous students attended such schools, and yet in 2015, the TRC alleges that everything negative in the lives of Aboriginals since 1883 and continuing in 2025 is caused by the IRS. The report makes no effort to try to separate issues stemming from the schools vs living conditions on reserves. It never compares issues between students and families who attended IRS and those who did not attend them.

It is clear that indigenous groups have serious problems, including poverty, marginalization, alcohol and drug abuse, and family breakdown. It is ridiculous for the TRC to claim that all of these problems are a result of residential schools.

The Truth and Reconciliation Commission spent $60,000,000 of public money to produce a document that can’t be trusted. Neither the stories nor the conclusions should be treated as “TRUTH”.

What I find most disturbing, and you should too, is that we wasted 60 million dollars. At the time the commission was announced, indigenous people were jumping for joy to have the opportunity. But was this really the best use of the money? Would indigenous people not be better off if we spent it on actually providing some services to them?

It is time to let the past go. Canada and the indigenous people need to move on and develop a better future. Rehashing the past does not really help anyone.

The Lasting Damage of the Truth and Reconciliation Report

I asked my granddaughter (white, descendant from immigrant families) what she knows about residential schools, and she has been taught about them in school. She learned that the IRS forced indigenous children to attend the schools and then stole their culture.

Just before this conversation, I was listened to a CBC program on the radio where they were interviewing indigenous students who were learning hoop dancing. The dancers commented that one reason they loved this form of dance is that it allowed them to connect with their culture, which was stolen from them and their parents in day schools. The interviewer acknowledged the fact that residential schools had done harm.

Both of these comments about the loss of culture are false. It is sad that both groups are being taught these lies about our past. The Truth and Reconciliation Report has done some serious damage to many people in Canada.

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How do we know this? Simple, just watch consumers and see how they shop.

Here are 5 food price metrics that show prices are not high.

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Potato Chip Metric

I have been watching the potato chip aisle in my grocery store for about 15 years. In that time, the number of products has not gone down. The shelf space used for them has remained the same. This means people are still buying as many potato chips as before.

What makes this a good metric of food prices?

The cost of potato chips is very high. The bags are mostly air, and the weight of the contents is very small. Add to that the fact that potato chips are not even food. They are carbohydrates and oils, both of which are overconsumed in developed countries. No one can argue that this food is needed in our diet. It is clearly a luxury item.

If people are buying non-food items, then the price of real food is not too high.

If people have enough extra cash to spend on potato chips, they do not have a problem with the cost of food.

Potato Chip Sales

Potato chip sales in the US have been steadily rising, but when adjusted for inflation to 2024, sales have been falling since 2014. They have leveled off in recent years.

There has been no dramatic drop in sales in the last few years, which might indicate a problem with cost.

Frozen Juice Metric

Frozen juice is a good, inexpensive way to consume fruits. Defrost the concentrate, pour it into a jug, add water, and you have fruit juice. It takes about a minute.

In an economy with high food prices, one would expect to see frozen juice sales increase while fresh fruit juice sales decrease. The opposite is happening.

Consumers are not willing to save significantly by spending a minute to make their own.

Minute Maid frozen orange juice became a staple 80 years ago, but it has now announced it will discontinue the product because consumers prefer fresh juice.

Savings With Frozen Juice

Fresh juice (Ocean Spray Cranberry) at my local store is $4.49/1.89L (Canadian). The regular price for Minute Maid is $1.99, which makes 1.2L. Frozen juice is 30% cheaper than fresh juice.

If food prices were high and budgets were tight, would consumers not choose a 30% savings option? I guess not!

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Food Price Metric

The claim is that food prices are higher today than in the past. Is this really true?

In real terms, bananas, tomatoes, eggs, and chicken are all cheaper today than they were in 1984. Bread, however, has grown more expensive.

It is common to see claims that meat is much more expensive. The price of round steak, a consistent historical benchmark for beef, cost $1.14/100g in 1900. By 1950, the price had soared to $2.70, but has declined since then and is now $1.65 (US, 2024, adjusted for inflation).

Overall, the price of basic food items has not increased much over the last 100 years.

However, there are more expensive food items on grocery shelves. Things like pre-processed meals are very expensive, but then anyone on a budget should not be buying such products. They are also not “just food items”. They are food + service, and you pay extra for service.

Meal Kit Delivery Service

Who has time to buy actual groceries? Instead, pay a service to deliver prepared ingredients. This service has become very popular.

There has been a steady increase in sales up to 2020, with a significant surge during COVID. Sales have been flat for the last few years.

The popular perception of high food prices has not dampened this form of expensive food.

Delivery and tip fees usually equal or exceed the meal cost, which is already high.

Takeout and delivery remain popular in 2025. “A 2024 DoorDash study found that in a typical month, about 70% of U.S. consumers order food for delivery, 70% pick up takeout, and 68% dine at a restaurant – suggesting that a majority of people are doing all three in any given month. “ Clearly, food costs are not a real concern.

The Lettuce Metric

If food prices were really high, and consumers couldn’t afford the food they needed, you would expect them to make smart choices. For example, buy nutritious food that is less expensive and lettuce is a good example. It is known for being nutritious, but it is also one of the most expensive food items when you compare price to nutrition.

A few years ago, I ran the numbers to see how lettuce compares to some other food items.

The above table shows the cost of 500 g of fresh groceries. The numbers are then corrected for moisture. This is important because water is free from the tap, and you don’t want to pay high prices for it in your food.

On a dry weight basis, lettuce is 6 times the cost of apples and 18 times the price of shelled peanuts. Lettuce is really expensive. It is one reason I don’t buy it.

What about nutrition? One of the key nutritional items we want from food is protein.

When corrected for the amount of protein, lettuce is midway between peanuts and apples.

The total sale of lettuce has been quite steady for 100 years, with the sale of head lettuce dropping while romaine lettuce increases.

What Dining Out Really Costs You

Americans like to eat out or get takeout/delivery regularly. Data for 2025 suggests about 70% order delivery, 70% get takeout, and 68% dine in-restaurant monthly. Ramsey recently suggested that a couple with no kids spends $4,469 a year.

That may not seem like a lot, but what is the real cost of dining out?

Instead of dining out, eat in and cook your own meals. Let’s say that costs $1,500. That means you save $3,000 a year, which can be invested. If invested properly, you should have no trouble getting an average return of about 8%. For comparison, in the years 2018 to 2025 (inclusive), my average return was 10.2%.

Now do this for 30 years. The following table shows you the cost of dining out.

At 8%, you would have an investment of $340,000 in 30 years. At 10%, you would have half a million dollars. That is the true cost of eating out.

This may seem like a weird way to evaluate the cost of things, but it is what money-conscious consumers, like me, do. Every dollar saved results in huge savings long-term.

The Real Problem With Food Prices

Food prices are not high if you are shopping for real food.

Many people in developed countries are not buying food - they are buying convenience along with food and expect low prices for that. It is time that we are honest with ourselves. If you want convenience, you have to pay extra. People’s time is expensive.

Today’s middle class is so much better off than 100 or 200 years ago. The quality of the food, its abundance, and the selection today are all so much better than in the past, and yet prices have remained fairly stable when corrected for inflation.

There is no problem with food prices in North America. There is a perception problem, but not a real problem.

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I don’t listen to music because I don’t enjoy it. I have never been to a concert, nor have I ever bought a music record or CD. A lot of music, especially rock-type music, sounds like loud noise and can even give me a headache.

A few years ago, my wife and I went to a musical play, something like The Lion King. Afterwards, she asked me what I thought of it. I replied, “That would be a great show if they didn’t sing”. She doesn’t take me to musicals anymore.

I now know that I have a condition called Musical Anhedonia.

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What is Musical Anhedonia?

About 3-5% of the population experience no pleasure from music despite normal hearing and intact emotions. Brain imaging reveals that their auditory and enjoyment centers are not connected properly. We can hear the music just fine, but we don’t get pleasure from it.

Think about your neighbor building a deck. You can hear the hammer smash the nails, bang, bang, bang, but the noise brings you no enjoyment. It does not bring a smile to your face, nor does it make you tap your foot to the beat. That is how music affects me.

People with musical anhedonia can recognize and process melodies, indicating that the auditory system is functioning normally. Brain scans show that music fails to stimulate the reward center of the brain. This part of the brain functions normally when stimulated by other activities such as food, sex, art, and winning a game, showing that it is working correctly.

It is similar to tasting food and getting the flavor correct, but not really enjoying the food. You can eat it if you're really hungry, but you won’t reach for it because you like it.

Studies using the BMRQ (see below) have revealed substantial variability in musical reward sensitivity within the general population, with most people showing high sensitivity, a small group showing unusually strong responses, and approximately 5% exhibiting very low sensitivity consistent with musical anhedonia.

The English word hedonic comes from the ancient Greek for pleasure, and today hedonic refers to sensory pleasures as well as many higher types of pleasure (e.g., cognitive, social, aesthetic, and moral).

Do You Have It?

The research team working on this problem developed a standardized assessment called the Barcelona Music Reward Questionnaire (BMRQ). This tool evaluates how rewarding an individual finds music by assessing their involvement with music and musical events.

Take the test for free: Barcelona Music Reward Questionnaire

If you have the condition, it becomes very obvious as you go down the list of questions.

I mentioned to a friend that I now watch everything on YouTube, including movies, at about 1.5 speed. He was shocked. He said, "Does that not distort the music in movies?” No, it doesn’t because I don’t even notice the music in movies.

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Implications Beyond Music

The authors of the study argue that their findings have broader implications for understanding how pleasure is generated in the brain. Reward is not a single on/off switch that everyone in the population has. It is more like a thermostat with a variety of sensitivities, and for any given stimulus, each of us has our thermostat set to a different sensitivity.

That means each of us enjoys a specific activity/event to a different degree.

I enjoy watching some sports, but I have trouble sitting for three hours at an event. I also don’t jump up and down after a goal. I do, however, get great enjoyment from making a point in table tennis or winning a pool game.

The other day, the Toronto Raptors were playing a playoff game, and fans were standing outside watching a big screen in the freezing rain. They were excited and energized. They loved being there. You would never catch me there. Give me a dry chair in front of the TV instead.

“If the reward circuit is not working well, you get less pleasure from all kinds of rewards,” says Ernest Mas-Herrero. “Here, what we point out is that it might be not only the engagement of this circuitry that is important, but also how it interacts with other brain regions that are relevant for the processing of each reward type.”

Further research may uncover other specific anhedonias. We may find that some people have food anhedonia and get little pleasure from eating.

The team is now working with geneticists to pinpoint genes that may contribute to musical anhedonia. They also plan to explore whether the condition remains stable over time or can change throughout a person’s life -- and whether musical anhedonia or similar conditions might eventually be reversed.

Genetics, Environment, and Individual Differences

Researchers still do not know exactly why some people develop musical anhedonia, but both genetic makeup and life experiences appear to contribute. A recent study involving twins found that genetics may account for up to 54% of the differences in how much people enjoy music.

We never had music playing while growing up. My father seemed to enjoy it a bit, but my mother didn’t. I am sure she also has musical anhedonia.

Even among people with the condition, there is a range of sensitivity. For most, it is not an all-or-nothing condition.

Research currently treats pleasure as either present or absent. However, growing evidence suggests that this assumption is incorrect. The degree of pleasure from a situation or activity varies.

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Is the “gluten” in corn gluten meal the same as the gluten in food?

What is gluten in food? There seem to be a lot of people allergic to it, but is this really true?

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What is Corn Gluten Meal?

Corn gluten meal (CGM) is a byproduct of the wet-milling process used to make corn syrup and animal feed. In the early 20th century, corn processors used the word “gluten” to describe any high-protein portion of a grain.

These proteins are called zeins and are completely different from wheat proteins.

Corn is naturally “gluten-free” and does not trigger the same autoimmune reaction as wheat gluten. The term gluten is incorrectly applied to corn.

Uses for Corn Gluten Meal

Corn gluten meal has three primary uses.

Animal feed: This is the most common use. It is a highly digestible protein source for poultry, pet food, and livestock.

Fertilizer: Corn gluten meal is about 10% nitrogen, making it a good fertilizer.

Preemergent Herbicide: Used mainly on lawns. This is fully described in Corn Gluten Meal - Does It Work for Weeds?

What is Wheat Gluten?

When people talk about a “gluten-free” diet, they are referring to a group of proteins—specifically gliadin and glutenin—found in wheat, barley, and rye. In people with Celiac disease or gluten sensitivity, these specific proteins trigger an immune response that damages the small intestine.

Wheat gluten is used in a lot of processed food, especially baked goods.

What is Rice Gluten?

In my research on this topic, I also came across the term rice gluten.

Just like with corn, the term “rice gluten” is a botanical misnomer. Rice does not contain the “true” gluten (gliadin and glutenin) found in wheat, barley, or rye.

When people or manufacturers refer to “rice gluten” or “rice gluten meal,” they are actually talking about the concentrated proteins left over after the starch is removed from the rice grain.

Rice Gluten Meal

Similar to corn gluten meal, rice gluten meal is sold as a high-protein (usually 60%+) animal feed ingredient for poultry and aquaculture. It is not a good herbicide.

Gluten Contamination of Corn Products

To make things even more confusing, some corn products are contaminated with wheat proteins.

In 2012, the Canadian Food Inspection Agency (CFIA) undertook a study of corn flour and found that 16% of corn flour samples contained over 20 parts per million (ppm) of gluten, ranging anywhere from 8 ppm to 731 ppm. Manufacturing processes have remained relatively unchanged since this study was completed.

This does not mean corn contains gluten. It just shows that this kind of manufacturing is not completely clean.

It is important to distinguish between the different types of adverse reactions to gluten, as the term “allergy” is often used colloquially to cover three distinct conditions: Celiac disease, Non-celiac gluten sensitivity (NCGS), and Wheat allergy.

Each has a different prevalence and mechanism.

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Medical Issues With Gluten

There are three categories of medical issues with gluten.

Celiac Disease

Celiac disease is not an allergy; it is a serious autoimmune disorder where the ingestion of gluten leads to damage in the small intestine. About 1% of the global population has this condition, but it varies significantly by region, from near 0% in East Asia to 2% in other populations.

Wheat Allergy

A wheat allergy is an immune response to proteins found in wheat (which may include, but are not limited to, gluten). This is a classic food allergy that can cause symptoms ranging from hives and digestive issues to anaphylaxis.

It affects approximately 0.8% of the global population. It is more commonly identified in children than in adults, though many children eventually outgrow the allergy.

Non-Celiac Gluten Sensitivity (NCGS)

This is a condition where individuals experience symptoms similar to Celiac disease after consuming gluten but test negative for both Celiac disease and wheat allergies.

Clinical diagnosis suggests that the condition affects between 0.5% to 13% of the general population. However, the number that self-diagnose the condition is much higher. A major 2025 meta-analysis found a pooled global prevalence of 10.3% for self-reported sensitivity. The symptoms are highly variable and can include bloating, abdominal discomfort, abdominal pain, and fatigue, which are similar to irritable bowel syndrome. Self-reported NCGWS was significantly more common in females than in males.

Although 10% self-diagnose for this condition, only 4% follow a gluten-free diet, and only 3% are confirmed by clinical examination.

NCGS does not seem to be as common as believed by the general population.

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There are also claims that it reduces coughing, heals wounds, and makes you sleep better. What does the science say?

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The Claims for Honey

• Honey is nutritious

• Raw honey is better than pasteurized honey

• Honey reduces coughing

• Wounds are healed by honey

• Honey improves sleep

• Honey is a Prebiotic

Is Honey Nutritious?

The US Department of Agriculture defines a nutrient-rich food index (NRF) based on 9 nutrients to encourage (protein, fiber, vitamins A, C, and E; calcium; iron; potassium; and magnesium) and 3 nutrients to limit (saturated fat, added sugar, and sodium). The idea being that you should eat fewer calories and still get high amounts of the things your body needs.

Using the above definition for nutrition, honey is not very nutritious. It contains a small amount of protein (< 1%), vitamin C (1%), but no fiber, vitamin A or E. It does contain a large amount of sugar.

But what about all the other things in food, like antioxidants and phytochemicals? Are they not important? This is a fundamental flaw in the definition of nutrient-rich food.

Phytochemicals in Honey

Honey does contain phytochemicals such as polyphenols and antioxidants, but the amounts are lower than those of blueberries and apples, while the calorie content is much higher. Most people eat pasteurized honey, making the difference even greater.

Honey is not a good choice for increasing phytochemicals in your diet.

The Sugar in Honey

Unlike white sugar, which is 100% sucrose (a disaccharide of glucose and fructose bonded together), the sugar in honey is already mostly broken down into individual monosaccharides.

Because honey has a higher fructose content than table sugar, it actually tastes slightly sweeter to most people.

Most regulatory agencies, including the World Health Organization, the Heart and Stroke Foundation, and the US Food and Drug Administration, include honey within their definition of free or added sugars. Both organizations recommend reducing daily intake of free sugars to less than 5% of their total energy intake. For an average 2,000-calorie-a-day diet, 5% is about 24 grams (or 6 tsp) of added sugars.

• One can of pop contains about 40g (10 tsp) of sugar.

• One teaspoon (5 ml) of honey contains about 6g of sugar (21 calories)

When you look at the sugar profile, honey is more like high fructose corn syrup (HFCS), which is not considered to be very healthy.

Is Raw Honey Better?

Raw honey is defined as honey that has not been heated beyond the temperature of the hive (approximately 35°C) and has not been finely filtered. The claim is that this honey is superior to pasteurized honey, which is heated to high temperatures (often 70°C to 72°C) and then rapidly cooled to prevent crystallization and kill yeast.

The high heat and filtration do not affect the macronutrient profile (fructose and glucose), but they can affect some minor components.

• Enzymes: Heating denatures several valuable enzymes, including Glucose Oxidase, which produces hydrogen peroxide (H2O2), which has antimicrobial properties.

• Production of HMF (5-Hydroxymethylfurfural): HMF is a chemical compound formed by the breakdown of sugars in the presence of acid during heating or long-term storage. High levels can cause health issues.

• Polyphenols and Antioxidants: Raw honey contains a variety of phenolic acids and flavonoids (like pinocembrin, chrysin, and galangin), which can be reduced by high heat and ultra-filtration.

A recent meta-study found that raw honey does offer some benefits over processed honey.

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Does Honey Reduce Coughing?

The claim is that honey reduces coughing associated with upper respiratory tract infections (URTIs) like the common cold.

A meta-study that looked at 14 studies and concluded that “Honey was superior to usual care for the improvement of symptoms of upper respiratory tract infections … but further high-quality, placebo-controlled trials are needed.”

Another study that looked at acute cough in children found “Honey probably relieves cough symptoms to a greater extent than no treatment, diphenhydramine, and placebo, but may make little or no difference compared to dextromethorphan. There was no strong evidence for or against using honey. Most of the children received treatment for one night, which is a limitation to the results of this review. ”

• Diphenhydramine (commonly known as Benadryl) is a first-generation antihistamine used to temporarily relieve allergy, cold, and hay fever symptoms, such as sneezing, runny nose, and itchy eyes.

• Dextromethorphan is a widely used, over-the-counter medication to temporarily relieve dry coughs caused by colds or flu. Common brand names include Robitussin, Delsym, and Vicks DayQuil.

It is crucial to remember that honey should not be given to children younger than 1 year old due to the risk of infant botulism, a rare but serious form of food poisoning caused by Clostridium botulinum spores.

Honey’s effectiveness is thought to be due to its “demulcent” effect—it coats the throat, which soothes irritation and reduces the urge to cough.

Honey may provide some limited reduction in coughing, but the evidence suggests it is not very effective.

Wound Healing

Wound healing is a common claim for honey, and it has been studied a fair amount. For example, one study compared honey to a standard treatment of silver sulfadiazine in a clinical setting, and honey worked better. However, the scientific evidence is not very strong when it is compared to other types of treatment.

A meta study has this to say, “It is difficult to draw overall conclusions regarding the effects of honey as a topical treatment for wounds due to the heterogeneous nature of the patient populations and comparators studied and the mostly low quality of the evidence. The quality of the evidence was mainly downgraded for risk of bias and imprecision. Honey appears to heal partial thickness burns more quickly than conventional treatment (which included polyurethane film, paraffin gauze, soframycin‐impregnated gauze, sterile linen and leaving the burns exposed) and infected post‐operative wounds more quickly than antiseptics and gauze. Beyond these comparisons, any evidence for differences in the effects of honey and comparators is of low or very low quality and does not form a robust basis for decision making.”

My local source of honey, the University of Guelph Honey Bee Research Center, has this to say: “Our raw honey has never been filtered or heated. Due to its antimicrobial and wound healing properties, this honey is applied to patients at the Ontario Veterinary College (part of the U. of Guelph). Read about how honey saved a burned dog by Dr, Mathews who published a review of this work.

Note: Much of the research is done using medical-grade honey, which is sterilized by gamma irradiation rather than heat pasteurization.

Research indicates that honey heals wounds through five distinct, overlapping chemical and physical processes:

• Osmotic Effect: Honey is a supersaturated sugar solution. This “high osmolarity” draws fluid out of the wound bed, which flushes out bacteria and debris while maintaining a moist environment that promotes tissue regrowth.

• Acidity (pH): Honey typically has a pH between 3.2 and 4.5. This acidic environment inhibits many pathogens and encourages the release of oxygen from hemoglobin, which is vital for tissue repair.

• Hydrogen Peroxide (H2O2) Production: The enzyme glucose oxidase (added by bees) reacts with water in the wound to produce low levels of hydrogen peroxide. This provides a slow-release antibacterial effect without the tissue damage caused by high-strength liquid peroxide.

• Biofilm Disruption: Recent studies show honey can penetrate and break down “biofilms”—the protective slimy layers that bacteria build to shield themselves from antibiotics.

There is some evidence for the healing power of honey, but it is limited. Since the research that has been done focuses on medical-grade honey and not on the honey you buy, it is probably best not to use store-bought honey for this purpose, except in an emergency.

Does Honey Improve Sleep?

An article by Healthline concluded that a glass of warm milk with honey just before bed helps promote better sleep quality, and claimed scientific studies support this claim. None of the three studies they supplied supports their claim.

This is a common claim made by lots of online sites, but none of the ones I looked at provide any scientific evidence to support the claim.

The claim is explained this way. Honey contains tryptophan, which your body converts into serotonin, then melatonin. Melatonin regulates your sleep-wake cycle and signals your brain that bedtime has arrived.

However, the tryptophan level in honey is very low at only 5 mg/100g. Compare that to turkey (576 mg/100g), cheddar cheese (320 mg/100g), eggs (167 mg/100g), and whole milk (46 mg/100g). If eating tryptophan before bed helped with sleep, honey would not be a good choice.

Global RPH (the clinician’s ultimate reference) reported on a study that showed honey provides better sleep, but the study was small and did not measure cortisol levels. “Some patients reported improvements in sleep while others noticed no change or even experienced worsening symptoms due to blood sugar fluctuations.”

Another meta-study found only a few studies that looked at the effect of honey on sleep. Most were either done on animals or were more focused on reducing coughs at night. There was no strong evidence to support the claim.

One research study commented that, “Very little information is available regarding the serotonin content of foods and, consequently, studies related to sleep-promoting effects of food sources of this neurotransmitter are limited.”

I found no scientific evidence that eating honey before bedtime would improve sleep for the average person. It might have some limited effect if you go to bed with a cough.

Does Honey Help the Gut Microbiome?

Just about every so-called healthy food makes the claim that it helps the gut microbiome. Most of those claims are unfounded, given the current limited research in this area.

It is also claimed that honey is a prebiotic, a food that helps the gut microbiome.

Here is what a review of the existing science has to say: “Despite current marketing and increased consumer interest around ‘prebiotic honey,’ there are limited published studies and human response data in this research area. The bioactive components in honey responsible for its prebiotic effect have not been fully identified. Additionally, whether honey can act as a prebiotic to remediate the gut microbiome in a state of dysbiosis, such as during infection or when the bowels are inflamed, is not well understood.”

Clearly, the claims are not supported by today’s science.

The Bottom Line

Honey has a mystic about it that makes it special. It has been used for thousands of years to heal all kinds of problems. It is no wonder people want to believe that honey has special powers. But the science disagrees.

Honey does not improve sleep, and there is no supporting evidence that it improves gut health, although bacteria love to eat sugar. It does help heal a wound, but it may not be better than other options. It has some limited effect on reducing coughing.

None of these is a strong reason to eat honey.

What about nutrition? Honey does contain some beneficial compounds, but it also contains very high levels of sugar, and people in developed countries should be reducing sugar intake, not increasing it. There are many better options for increasing vitamins, antioxidants, and polyphenols in your diet.

Honey is better than eating cane sugar, but many other foods are a better choice than honey for nutrition.

I eat honey because I like it, but I don’t consider it to be a nutritious food.

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Understanding whether these distinctions are rooted in chemistry or marketing requires a deeper dive into their molecular structures and metabolic pathways.

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Cane Sugar vs Corn Syrup (HFCS)

To understand the differences between these two sweeteners, one must consider their origins and chemistry.

Cane Sugar (Sucrose)

Cane sugar is produced from the sugar cane plant or sugar beets. The process involves crushing the stalks/beets to extract juice, which is then purified with lime, evaporated into a syrup, and crystallized. The result is sucrose.

Whether it is “raw,” “brown,” or “white,” the base molecule remains the same.

Sucrose consists of a molecule of glucose and a molecule of fructose. All three of these molecules are called sugars by chemists.

Taken from my book Food Science for Gardeners: “Both sugar cane and sugar beets are ground up and a liquid is extracted and refined to form white sugar. During the refining process, a brown liquid waste product called molasses is also produced. Brown sugar is made by coating refined white sugar with varying amounts of molasses. The amount of molasses in brown sugar is very small and therefore does not provide much nutrition.

From a nutritional point of view, refined white sugar, and brown sugar are all the same sugar. Neither is more nutritious than the other.”

On a global scale, cane sugar is more prevalent, accounting for roughly 75% to 80% of the world’s sugar production. In the US, beet sugar is slightly more prevalent, whereas in Europe, it is definitely the most dominant source of sugar.

Corn Syrup and HFCS

Corn syrup is produced from corn starch, which is a long chain of glucose. Through acid or enzymatic hydrolysis, the starch is broken down into individual glucose molecules. Standard corn syrup is 100% glucose (dry weight). However, to mimic the sweetness of cane sugar, manufacturers use an enzyme to convert some of that glucose into fructose. The most common varieties in the food industry are:

• HFCS-42: 42% fructose / 58% glucose (used in baked goods).

• HFCS-55: 55% fructose / 45% glucose (used in soft drinks).

These % values are based on dry weight. The ones in the table are wet weight.

Do The Bonds Matter?

To summarize the above, cane sugar is one molecule consisting of a glucose molecule and a fructose molecule joined together. In chemical terms, they are bonded together. Corn syrup consists of glucose molecules and fructose molecules that are not bonded together. They just float next to each other.

Does this make a difference?

In a laboratory, there are significant differences between cane sugar and corn syrup. But this difference disappears in the human body.

Stomach acids and intestinal enzymes break the sucrose bond so rapidly that, by the time the sugars reach the bloodstream, there is no difference except in the ratio of glucose to fructose, which is at most a 5% difference.

So why does HFCS get treated like a villain?

“Partly historical. Some early animal studies suggested that high fructose intake could lead to worse metabolic effects, raising alarms. But rodents process nutrients differently from humans, and when tested in well-controlled human trials, this difference disappears.”

A double-blind 2021 clinical trial using healthy adults consumed beverages sweetened with either HFCS or sucrose. Both groups showed the same results. There were no differences between cane sugar and corn syrup.

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The Claim: Cane Sugar is “Healthier”

To start with, neither form of sugar is healthy. Our bodies do need carbohydrates, but in developed countries, we already consume too many. Adding sugar of any type to our diet provides no health benefit.

The “Made with Real Sugar” label has become a powerful marketing tool. However, the scientific consensus (supported by the FDA and the American Medical Association) suggests that the body does not distinguish between the two once they are digested.

The Fructose Ratio

The argument for cane sugar being “healthier” usually hinges on the fact that it is exactly 50% fructose. Because HFCS-55 contains 55% fructose, critics argue it is more lipogenic (fat-producing). However, the 5% difference is statistically negligible in a standard diet. Remember, we also get sugars from many of the foods we eat, including fruits. Carbohydrates are also broken down into simple sugars.

The variety of sugars in our diet dwarfs the 5% difference in our added sugar source. The claim that the 50% ratio in cane sugar is healthier is false.

The Claim: Corn Syrup is “Harmful”

The “harm” associated with corn syrup is real, but sugar cane is just as harmful.

The harm from these sugars is a result of the amount of sugar we consume. It is added to almost all processed food.

The harm of HFCS is not due to its chemical structure, but due to its ubiquity. It made sweetness so cheap that we began consuming it in unprecedented amounts.

Excess amounts of both forms of sugar are equally harmful.

Conclusion

Chemically, cane sugar and corn syrup are essentially the same. Both consist of glucose and fructose in near-equal proportions. They affect our bodies in the same way.

Neither cane sugar nor corn syrup is healthier!

The “healthier” choice is not to swap one for the other, but to reduce the total load of added sweeteners regardless of their botanical origin.

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The word organic is used by many groups to mean completely different things, which leads to a lot of confusion.

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The Chemist’s Definition

Chemists use the word organic to describe a chemical that contains carbon. When a chemist says a pesticide is organic, it means it contains carbon. It could be derived from nature or be man-made; either way, it is organic.

What Does Organic Mean to the General Public?

When the general public refers to something as being organic, it can mean different things. Here are some of the ways the term is used:

• Certified Organic: This is food that has been grown using a special set of rules.

• Organic Food: It is commonly believed that this term identifies food that was grown without chemicals, but that is a myth.

• Organic Product: A product, such as fertilizer, that is made from organic matter (defined as dead plants and animals).

• Natural: A term used in place of organic, but without having a real definition.

The only term from the above list that is clearly defined is “certified organic”, but the general population does not fully understand the definition or use it correctly. The other terms are not well defined, and people have their own “opinion” about what they mean. This leads to a lot of confusion.

Certified Organic

Several countries, including Canada, the US, the European Community, and Japan, regulate the meaning of ‘organic food’. To be called organic, the food must have been produced using specific Certified Organic guidelines. Only then can it be called organic.

It is a common belief that certified organic food is grown without chemicals, but that is a myth. The food can be grown with chemicals, provided they are “approved” chemicals, and the approved list varies by country.

It should be noted that the approved chemicals can be more toxic than chemicals that are not approved. They also tend to be less effective and are therefore used in larger quantities.

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Organic Food

It’s probably a surprise that the definition of organic food is not well-defined.

If you grow your own food in the backyard without pesticides or synthetic fertilizers, you might consider that food as organic, but it’s not.

The US has various categories of organic food.

• 100 % Organic: A product that contains 100 percent certified organic ingredients. Added salt and water do not need to be certified because they are “natural”. Most unprocessed produce can be labeled 100% Organic if grown on certified organic farms.

• Organic: Such products contain a minimum of 95% certified organic ingredients.

• Made with Organic: Such labels indicate the product contains at least 70% certified organic ingredients.

  

Organic Products

The use of the word organic on products can be even more confusing. In theory, it indicates that the contents of the bag are made from organic material such as plants and animals. For example, compost. But it can also contain non-organic material like sand and perlite.

The truth is that organic on a bag of material means very little. It is used to sell the material to people who believe organic is superior.

Certified organic products are those that have been approved for use on certified organic farms and are labeled as “OMRI Listed”. The contents may or may not be organic matter. They are verified by the Organic Materials Review Institute (OMRI) to meet the USDA National Organic Program or the Canada Organic program.

My post What is Organic Fertilizer provides a more detailed description of organic fertilizer.

Natural Products

The term “natural” is being used more and more and seems to be synonymous with organic, which just confuses things even more.

The general public views “natural” products as being safe and healthy. This is simply not true. Natural products can be more toxic than man-made products. This is commonly the case with chemicals. Think of nicotine in tobacco plants.

Organic Gardening

The term organic gardening usually means that environmentally friendly practices are used. For example, mulching with organic material and fertilizing with manure would be part of organic gardening. The term is not well defined and can be misleading.

For example, if I use peat moss, is it organic gardening? Peat moss is a natural product, so it would seem to be an organic choice for amending the soil. But peat moss is usually trucked a long distance to get to your garden. The transportation required is certainly not environmentally friendly. Some people also incorrectly think that using peat moss is destroying a limited resource, which is mostly a myth.

What if you garden most of the time organically, but once or twice a year, you use synthetic fertilizer? Are you still an organic gardener?

I feel that the term is not as important as the actual practices you use. What is important is that all gardeners try to use environmentally friendly practices when possible. It is also important to understand how these practices benefit or harm your soil, your plants, or yourself. The idea that everything organic or natural is good for your garden is a myth.

Organic Myths

Here are some organic myths:

• Organic food is not more nutritious.

• Organic food is not healthier.

• Organic food does not have fewer pesticides.

To understand these better, have a look at: Is Organic Food Healthier?

What is Organic?

Except when used by a chemist, the term “organic” is not well defined. The term “certified organic” is better defined, but the definition changes by country, which causes confusion.

When the term organic is used by the general public or by news outlets, it has to be defined in each situation, or the discussion is mostly meaningless, but that rarely happens.

When the term is used on a product, it is also useless, unless it is a “certified organic” label. Manufacturers use it on products to make you think the product is safe and better than a competitor without the label. That is rarely the case.

The term “natural” is even more useless and misleading.

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It is a real dilemma for gardeners, and especially organic gardeners. Just when you thought you were doing something good for the planet, you find out that you may be causing harm.

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Does Composting Produce Carbon Dioxide CO2?

Yes — but that does not mean it is a bad choice for the environment.

Does Composting Contribute to Climate Change?

The answer to this question is far more complex and really depends on how you ask the question.

In simple terms, a compost pile will produce CO2, which increases the CO2 in the air, which in turn results in the warming of our planet.

But that only looks at a specific part of the whole picture. Humans produce organic waste to feed ourselves. We grow corn and only eat the kernels. The rest of the plant is organic waste, and in fact, even a good part of the kernel exits our body as waste.

Another significant source of organic matter is edible food that is discarded. That half-eaten apple ends up as food waste that we affectionately call kitchen scraps. Roughly 1/3 of the food produced globally is wasted. Reducing this has a much bigger impact on climate change than anything you do about composting.

Assuming we don’t get rid of humans, we have to accept the fact that we create organic waste, and that waste decomposes at some point, producing CO2. We can’t prevent decomposition from happening. Therefore, it is important to reword the original question. What is the best way to handle organic waste?

The Carbon Cycle

Organic waste contains carbon, which originally came from the air. Plants use CO2 from the air to make all of the chemicals they need to grow. As plants grow, they reduce the CO2 in the air.

Composting is simply returning some of this absorbed carbon to the air. It is not adding additional amounts.

About 50% of the carbon in the original waste material is released as CO2 or CH4 during composting. The remaining 50% is added back to the soil. This form of carbon is commonly called humus, but in a previous post, I explained that humus does not really exist. However, the carbon in soil does exist.

The process of growing plant material, composting it, and returning it to the soil results in a net decrease of CO2 in the air and an increase in soil organic matter.

Recent studies show that backyards can be significant contributors to storing carbon in soil.

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The Decomposition Process

Organic matter contains a lot of carbon, hydrogen, and oxygen, along with other minor molecules. This all becomes a food source for microbes that convert the large molecules into smaller and smaller molecules. This conversion requires energy, and in the process of extracting that energy, the microbes produce CO2. This is the same process that takes place when humans breathe out CO2.

The amount of CO2 produced depends very much on the method of decomposition. In general, a higher supply of oxygen results in more CO2 being produced.

Other greenhouse gases are also produced during decomposition, including methane and nitrous oxide.

Global Warming Potentials

To understand this topic, it is critical to understand something called global warming potential (GWP). GWP is a measure of how much heat a gas absorbs. Carbon dioxide is used as the standard and has a relative value of 1.

Methane (CH₄) has a value of about 30. This means that a molecule of methane contributes 30 times more heat to the air than a molecule of CO2. Or in simple terms, from a global warming perspective, methane is 30 times worse than CO2.

Nitrous Oxide (N₂O), commonly called laughing gas, has a GWP of 280. It is 10 times worse than methane, and 300 times worse than carbon dioxide.

Why are these numbers important?

A molecule of carbon in organic waste can be converted to either CH4 or CO2, but not both. Since composting has to happen in some way, it is best for climate change if it happens in such a way that we reduce the production of nitrous oxide and methane, and produce CO2 instead.

As a general rule, aerobic conditions produce CO2, and anaerobic conditions produce methane and nitrous oxide.

Organic Matter in Landfill Sites

Since composting contributes to climate change, maybe there is a better way?

For homeowners, there are really only two options: put the material in the garbage, which ends up in landfill sites, or compost it. Putting it in the green bin for municipal composting is just another form of composting.

When organic matter is added to a landfill site, it gets mixed with all other types of garbage in very large piles. These piles exclude oxygen, resulting in composting that produces a lot of methane.

Some landfill sites collect the methane and recycle it into energy. Only 650 sites of the current 2,000 US sites do this and the process is only 60 to 90% efficient.

20 percent of total US methane emissions come from landfills.

Virtually any composting is better than sending the material to a landfill site because methane is 30 times worse than carbon dioxide.

Composting Options

We can’t stop producing organic matter, so the best option is to compost it in the most eco-friendly way. In this section, I’ll look at some options to see which is best for reducing climate warming.

Municipal Composting

The effect of this process on the environment depends very much on how it is done.

Anaerobic digestion carries out the decomposition in large digesters without oxygen and results in the production of methane. In some cases, this methane is captured and recycled. In Toronto, Ontario, for example, some of these biogases (mostly CH4 and CO2) are used to heat the facility and the digesters, but some of it is just burned off, producing CO2.

Other facilities use aerobic composting, which produces very little methane but does produce CO2.

This seems like a good alternative, but you have to consider the production of greenhouse gases to transport your waste to the facility, run the facility, and then transport the compost to its final destination.

If and when municipalities recapture all of the biogas and use it efficiently, anaerobic digesters might be a better alternative to home composting, as far as the production of greenhouse gases goes.

Standard Hot Composting

Standard backyard hot composting uses a traditional bin that creates an aerobic condition (with oxygen). These systems produce little or no methane but do produce CO2. Procedures that make hot compost keep the effect on climate change to a minimum: 3 x 3 ft size, chop organic matter into small pieces, use the right C/N ratio, keep it moist but not wet, and turn it regularly.

If the compost pile gets too wet or if not enough air gets to the middle of the pile, it will start producing more methane. This study found that with enough air flow, no detectable methane was produced. Other studies did find some methane, but the amounts are normally small.

Nitrous oxide is also produced during composting (see discussion below).

Some research has been done to determine the best hot composting method; there are so many variables, and very limited testing has been done so far.

Cold Composting

The reality is that most gardeners do not get their compost piles hot enough to consider the process hot composting. It is really lukewarm composting. Others just pile up fall leaves and let them compost slowly.

It is not clear how this impacts climate change, but you can expect that most of these processes occur less aerobically than hot composting, which means they produce more methane. From an environmental point of view, this type of home composting is less desirable than hot composting.

Direct Composting

There are two other approaches to composting: spreading organic matter over the ground so nature can do its thing, or burying the kitchen scraps underground.

Dropping organic matter as thin layers on top of the soil, what I like to call the cut and drop method, will produce very little methane because decomposition is very aerobic.

Burying the organic matter can be a problem. If it is buried too deep, it starts decomposing anaerobically, producing methane. The amount produced depends on the soil type. Coarse soil with good oxygen levels is less of a problem, but heavy clay soil with low oxygen is a problem. Keeping the organic matter closer to the surface will help keep it more aerobic.

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The Elephant in the Room: Nitrous Oxide

Since nitrous oxide is so much worse for the environment than CO2, you would expect that this gets more attention, but that is not what I found. Few even mention it. I think in part this is because it is a more recent concern.

Nitrous oxide production is low during the hot composting process, but it may become higher during the curing process (once the pile cools down). It may also be high once applied to soil.

In 2006, the Intergovernmental Panel on Climate Change (IPCC) suggested that N2O emissions during the composting process are 3% of the nitrogen in the waste, but this is based mostly on manure systems, not yard waste. Recent reports suggest the number might be significantly lower than this, in which case, the production from composting is not a major factor for climate change.

Compost piles tend to generate most of the nitrous oxide at the end of the process. Keeping nitrogen levels down may help keep emissions low. Adding manure, which is generally higher in nitrogen, increases the production of nitrous oxide. Aeration keeps levels lower. This study found relatively low amounts of nitrous oxide produced in compost piles.

Does Composting Contribute to Climate Change?

Composting does produce CO2. However, when done properly, the complete cycle of growing plants followed by composting results in a net reduction of CO2 in the air and an increase in sequestered carbon in soil.

The composting process must produce as little methane and nitrous oxide as possible.

We can’t stop producing organic matter, and so our goal is to find the best way to return its carbon to the soil. Traditional hot composting is the best choice for most gardeners.

If you live near an anaerobic composting facility that completely recycles the produced biogases, it might be an eco-friendly option. Ideally, this facility returns compost to your garden once a year so that you can increase the carbon in your soil. But I suspect these facilities will never be as eco-friendly as backyard composting.

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Should we take over-the-counter probiotic supplements?

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What Are Probiotic Supplements?

Probiotics are microorganisms that are beneficial for our health. They are mostly bacterial but can also include yeasts.

Our bodies are covered with microbes, both on the outside and the inside, especially in our gut. Some of these microbes cause us problems, but most of them are not only beneficial, but some are essential to our well-being.

There are generally two ways in which we can add microbes into our body: through our food or with supplements in the form of powders, pills, and capsules.

A supplement is a manufactured product that contains one or more probiotics, and they are usually sold to do one of two things:

• Add missing microbes to your gut.

• Improve your health.

Regulatory Controls

In the United States, probiotics are regulated as dietary supplements under the Dietary Supplement Health and Education Act (DSHEA) of 1994. There is no pre-market approval. Claims of cures and preventions must be backed by evidence, but most companies get around this with special language that does not require proof of efficacy. Examples include “Supports digestive health,” “Promotes a healthy immune system,” or “Maintains gut balance.”

The Mandatory Disclaimer: Any product making a structure/function claim must include the famous box: “These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.”

Information about the microbe species must be accurate, and the number of microbes (the CFU count) must be accurate at the time of manufacture.

In Canada, Health Canada must “pre-approve” the product before it can be sold. Each product is given an 8-digit Natural Product Number (NPN) indicating that the product has been approved for safety, quality, and health claims. Products that use pre-approved probiotic strains are quickly approved.

The regulations in the EU are quite different. While in the US, the word “probiotic” is a descriptive term for a category of ingredients, in the EU it is an implied health claim and is effectively banned from labels on food and supplements. For this reason, you rarely see probiotics for sale in Europe. When they are approved, they go through rigorous testing and approval similar to a drug.

The rest of this post will deal with over-the-counter probiotics supplements as defined in the US.

Claims for Probiotics

The claims are many. Here are some of the more common ones.

• Supports Digestive Health

• Promotes Immune System Function

• Maintains Gut Flora Balance

• Helps Reduce Occasional Bloating and Gas

• Supports Vaginal and Urinary Tract Health

• Promotes Regularity

• Replenishes Beneficial Bacteria After Antibiotic Use

• Supports the Gut-Brain Axis (Emotional Wellness)

• Enhances Nutrient Absorption

• Supports Skin Health from Within

The gut biome does a lot more than digest food. It affects our brain, our skin, and the body’s ability to fight infection, to name a few. Anything the gut biome can do is fair game for probiotic claims.

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Microbes Are a Game of Numbers

The number of microbes in and around us is so huge that we can’t comprehend it. From my book Microbe Science for Gardeners: “Bacteria can’t be seen with the naked eye; 500,000 take up no more room than the period at the end of this sentence.”

The human gut is home to roughly 50 trillion microbial cells, a vast inner ecosystem that outnumbers our own human cells. One of the most common misconceptions is the sheer scale of the probiotic “army” being sent into the gut.

• The Product: A high-quality probiotic supplement might contain 10 to 50 billion living bacteria.

• The Gut: The adult colon contains approximately 50,000 billion living bacteria.

The number of bacteria you swallow is extremely tiny compared to what is already in your gut.

What is a CFU?

Colony-forming unit (CFU, cfu or Cfu) is a unit that estimates the number of living microbial cells (bacteria, fungi, viruses, etc.). Scientists measure this by spreading some of the material onto a petri dish, and if a cell is viable, it will grow to form a colony (a clump of cells). These colonies are then counted.

How Many Are in the Bottle?

The CFU value for each pill is found on product labels. It is important to remember that this is the number at the time of manufacture. However, the pill you take may not contain the specified amount. Microbes are living organisms and die over time, and will die more quickly if improperly stored.

You never know how many you are consuming. The main killers are the following.

• Moisture: Probiotics are typically freeze-dried (lyophilized) to remove water. If moisture enters the bottle (from a humid bathroom or by leaving the lid off), the bacteria “rehydrate” prematurely. Without a food source to sustain them, they quickly burn through their energy reserves and die.

• Temperature: High temperatures increase the metabolic rate of the bacteria. Even if they are dry, heat causes their cell membranes to become more fluid and unstable, leading to cell death. This is why many manufacturers recommend refrigeration.

• Oxygen: Many probiotic strains (especially Bifidobacterium) are anaerobic, meaning they naturally live in environments without oxygen. Exposure to air can cause oxidative damage to their DNA and proteins, leading to a loss of viability.

Storage in a refrigerator has a CFU loss of about 15% a year, while storage in a warm, moist bathroom can have a 75% annual loss.

Do The Swallowed Probiotics Get to Your Gut?

The journey from the mouth to the large colon (the “gut”) is essentially a biological gauntlet, and for a probiotic to be effective, it must survive the trip. The survival rate varies widely by strain (e.g., Lactobacillus vs. Bifidobacterium) and delivery method (pill vs. food). Here are the main obstacles.

• The Mouth: Saliva contains lysozyme, an enzyme that breaks down bacterial cell walls. Pills pass through the mouth quickly with limited effect.

• The Stomach: Gastric acid has a pH between 1.5 and 3.0, while most bacteria are evolved to live at a neutral pH (7.0). If the probiotic is taken on an empty stomach, the acid can wipe out nearly the entire population. However, taking it with a fat-containing meal can boost survival to 60% or higher.

• The Small Intestine Environment: High concentrations of bile salts (which act like soap, dissolving the fatty membranes of bacteria) and digestive enzymes (protease, lipase) kill off more probiotics. Some probiotics are “bile-resistant”.

• Competition: The small intestine contains active microbes that will compete with the probiotics for attachment sites and nutrients. Microbes also digest each other. The competition here is minor compared to what probiotics will face in the large intestine.

The above table calculates the survival number reaching the large intestine (the gut). A starting tablet of 10 billion CFU will result in about 250 million reaching the gut, ready to compete with the existing 50 trillion already there.

Increasing the Odds of Survival

Because the survival rate is so low, researchers and manufacturers use three main “cheats” to increase the number of bacteria to reach the gut:

• Overdosing: This is why some pills have 50 billion CFU—they expect 48 billion of them to die.

• Enteric Coating: A special “plastic-like” vegetable coating that doesn’t dissolve in acid but melts instantly when it hits the neutral pH of the small intestine. This can increase survival to 80%.

• The Food Matrix: Eating probiotics in yogurt or kefir provides a “buffer.” The milk proteins and fats wrap around the bacteria, physically shielding them from the acid and bile.

Species Diversity

A healthy gut contains 500 to 1,000 different species, and because each species can have multiple strains, the number of unique strains in your gut is in the thousands. Compare that to supplements that contain 1 to 10 strains.

Clearly, a probiotic pill can’t supply all of your strains. The ones in the products are selected because they can be grown easily in a production facility.

When scientists look at the global human population, they have identified over 4,600 unique species. Everyone’s gut microbiome is different.

Species diversity is critical for a healthy gut. Adding a few new ones won’t make much of a difference.

Does the Microbiome Actually Change?

The most controversial aspect of probiotic science is whether these microbes actually “stick” or change our internal makeup.

A landmark 2018 study published in Cell by the Weizmann Institute of Science found that in many people, the gut is resistant to colonization. The probiotics passed through the digestive tract without altering the resident microbiome.

While probiotics may not permanently change the composition of your microbiome, they do change the metabolic activity (the chemicals the bacteria produce) while they are present.

Catch 22 - The Environment

Why take probiotics in the first place? They are taken mostly because we feel there is something wrong with our natural gut microbes. If that is true, then the environment in our gut is not suitable to keep them thriving. If the environment in our gut is not suitable for microbes, then adding a bunch more from a pill won’t change that.

The way you fix this problem is to change the diet. Once the environment is fixed, the natural gut microbes will thrive, and you don’t need to consume any from a pill.

We see the same situation in gardening. Companies sell bottled microbes to add to the soil. The claim is that this will increase the population in the soil. But that does not work because the environment - the soil - just can’t support a higher population. The solution is to add more organic matter to the soil. Do that, and the natural soil microbes population increases.

The secret for soil is organic matter. The secret for your gut is more real fiber, but not fiber supplements!

Evidence for Health Benefits

While they may not move in permanently, probiotic supplements have shown significant effectiveness in specific clinical scenarios:

• Antibiotic-Associated Diarrhea (AAD): Antibiotics kill gut microbes. Taking probiotic supplements (specifically L. rhamnosus GG or S. boulardii) during a course of antibiotics can reduce the risk of diarrhea by up to 51%.

• Irritable Bowel Syndrome (IBS): Meta-analyses suggest that probiotics can reduce bloating and abdominal pain in IBS patients, though the effect is modest and strain-dependent.

• Mental Health (The Gut-Brain Axis): Emerging research into “psychobiotics” suggests that certain strains can lower cortisol and improve mood. A 2019 review found that probiotics could significantly improve symptoms of depression.

Many other claims for probiotic supplements have no or limited scientific support.

Conclusion: Are They Effective?

Probiotics are effective if used for the right reason with the right strain. They are not a “cure-all” that will fix your microbiome. Instead, think of them as temporary consultants for your gut—they come in, perform a specific job, and then leave.

Their ability to permanently change the gut microbiome of a healthy person is limited.

Many of the claims are not supported by science, and taking probiotics can disrupt a normal gut biome.

Should you Take Probiotic Supplements?

Many people take them to improve their overall health, but the science does not support this use. It is probably a waste of money.

They can be useful for specific medical problems, but only if the right strains are consumed in large enough quantities. For this reason, it is best to only use them under a doctor’s direction.

A better idea is to get your probiotics through food. A landmark 2021 study demonstrated that a diet high in fermented foods consistently increases gut microbial diversity.

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Is that true?

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Renewables Surpass Fossil Fuels

In 2025, solar and wind renewables produced more electricity in the EU than fossil fuels. They have been a leader in developing renewables and have had major projects to increase their use.

This is a major victory for proponents of renewables, but did this milestone come at a high cost? Is it causing consumers to pay higher electricity costs?

Here is the updated breakdown for the 2025 EU electricity mix.

Electricity Costs Also Climb

Using economic data from Eurostat, I compared the trend in electricity costs with the increase in renewables.

The above chart shows the data from the previous graph for electricity production along with the historical costs of electricity in the EU (blue line) and in the US (red line). Both costs are in EUR per 100 kWh.

The US has not moved as aggressively as the EU in switching to renewables. Between 2006 and 2025, the consumer electricity cost in the US went up 93%. During that same time period, the consumer electricity cost in the EU went up 102%. This is only a difference of 9%.

This would seem to indicate that the focus on renewables has caused higher electricity prices in the EU compared to the US, but there is more to this story.

EU Electricity Prices Jump

The sudden jump in EU electricity prices between 2020 and 2022 was the result of a “perfect storm” of geopolitical and economic factors. While renewable energy production was increasing, several critical issues caused costs to skyrocket. Some of the differences in the electricity cost increase between the US and the EU can be accounted for by the following.

1. The “Merit Order” Pricing System

This is the most technical but important reason. In the EU, electricity prices are set by the marginal cost of the last power plant needed to meet demand.

• Renewables (wind/solar) are used first because they are the cheapest.

• However, when demand is high, the grid must turn on Natural Gas plants.

• Because of this system, even if 90% of the power is cheap wind, if the final 10% comes from expensive gas, the entire market price is set at that high gas rate.

2. The Russia-Ukraine War & Gas Crisis

Natural gas is the “bridge fuel” for the EU. When Russia began restricting pipeline flows in late 2021 and invaded Ukraine in early 2022, gas prices reached historic highs (increasing by over 500% at one point. Since gas often sets the “marginal price” for the whole grid, electricity bills followed suit.

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3. Post-Pandemic Demand Rebound

In 2020, during global lockdowns, energy demand crashed, leading to record-low prices. By 2021 and 2022, as the global industry “turned back on,” the surge in demand outpaced the supply of fuels and the speed at which new renewables could be integrated, creating a massive supply-demand imbalance.

4. Poor Weather & Maintenance Issues

Beyond gas, other backup power sources failed during this period:

• Hydro Power: Record droughts in Europe (2022) significantly reduced the output from hydroelectric dams.

• Nuclear Power: France, a major energy exporter, saw nearly half of its nuclear fleet go offline in 2022 due to emergency maintenance and corrosion issues, forcing the EU to rely even more heavily on expensive gas-fired plants.

5. Carbon Pricing (ETS)

The cost of EU Carbon Permits (required for burning fossil fuels) rose significantly between 2020 and 2022. While this encourages a shift to green energy, it makes the remaining coal and gas generation even more expensive in the short term, adding to the total retail price.

The Renewables Are Reducing Electricity Costs

There are several indicators that point to reduced electricity costs in the EU as more renewables come online. You can see evidence of this in the above chart with no increase in electricity costs between 2022 and 2025.

Electricity bills Fall in Türkiye

In 2025, renewable energy reduced households’ annual electricity bills by an average of 9%, roughly equivalent to one month’s worth of electricity bills over the year. This impact grew as renewables made up a larger share of generation, with bill reductions reaching up to 17% in the spring and summer months.

Perhaps more surprising is the fact that wholesale electricity prices have dropped during both low-demand (45% cheaper) and high-demand periods (23% cheaper).

Spain: Cheapest Power Prices in Europe

“Spain spent the last six years investing heavily in wind and solar energy, leading to some of the cheapest power prices in Europe”.

The Iran war has energy experts concerned about future high costs for oil, but one country is well-positioned to weather the storm because of renewables. Since 2019, Spain has doubled its wind and solar capacity, adding over 40 GW - more than any other EU country except Germany, whose power market is twice the size of Spain’s.

Spain’s energy bills are some of the lowest in Europe and are much less influenced by the ever-fluctuating cost of gas, which increased by 55% the day after the Iran war started and has continued to rise.

Germany Leads Europe in Renewables

Germany’s power mix passed a green milestone in 2024, with renewables making up 59% of electricity generation. Onshore wind was the biggest single energy source at 25.9% - despite a comparatively less windy year. Solar recorded the largest growth thanks to new installations and “an extraordinary amount of sunshine” over the summer.

What is driving this growth? The government reduced bureaucracy and simplified grid connections. Citizens increased home installations due to simplified processes to connect to the grid. The German government has also declared renewables to be in the overriding public interest.

Trump Supports Renewables in the EU

Ok, he did not do this directly, but his threat of tariffs resulted in countries finding alternatives that did not involve the US. Dr. Beatrice Petrovich said in a release. “As fossil fuel dependencies feed instability on the global stage, the stakes of transitioning to clean energy are clearer than ever.”

The war in Iran just fueled and confirmed the move.

Europe’s Electricity Prices Went Below Zero in 2025

European electricity markets saw a drop in power prices in 2025 as wholesale electricity prices fell below zero for many hours. During these times, power generators effectively paid buyers to take electricity because supply far exceeded demand.

Electricity markets normally set prices based on demand. If supply is higher than demand, the effective price drops below zero. This happens when wind and solar output exceed demand, and this was the case in 2025.

This is not a normal situation, nor is it common, but it does demonstrate the amount of renewable power that now exists in Europe.

Renewable Subsidies

Both the EU and the US subsidize the move towards more renewables, and since these affect electricity prices, they must be considered when comparing prices in the two regions.

• US Subsidies: Aimed at investors and companies as an encouragement to invest in renewables. They become part of the federal budget and may result in higher federal taxes, but they are not directly passed on to consumers. Therefore, they don’t increase consumer electrical bills.

• EU Subsidies: They have historically been “highly visible” as line-item taxes on consumer bills. However, the EU is now desperately trying to reform this to compete with US industrial prices. This has a direct effect of raising electricity bills for consumers.

The above graph comparing electricity costs is not a fair comparison since it looks at consumer costs. The change in price in the US has been kept artificially low compared to the EU because of the way these two regions pay for subsidies.

If the EU removed the subsidy costs from electricity bills, they would be reduced by about 13%. This would more than offset the difference of 9% increase since 2006.

But …. Industries Are Leaving Germany

Germany’s manufacturing sector is struggling, and part of the issue is the higher energy costs. Renewables play a role, but electrical price regulations are also a problem. The table below shows both consumer costs and industrial costs for electricity. Both Germany and the US subsidise electricity costs for industry, but the US provides electricity at a much lower relative price than in Germany.

Numerous other factors also affect manufacturing in Germany, including competition from imports, high bureaucracy, acute labor shortage, high pressure to decarbonize, and investment uncertainty.

Are Renewables Driving Up Electricity Prices?

Any time we make major switches in technology, there is a cost associated with it. There is no doubt that everyone is paying for the move to renewables.

However, when you compare electricity cost increases in the US and the EU, they are about the same when you take into account the way subsidies are handled.

Add to this the fact that the EU has seen unusual cost increases between 2020 and 2022 that affected the US much less.

When all of this is factored in, one must conclude that the strong move to renewables in the EU did not drive up costs more than the weaker move in the US.

Based on this data, the move to renewables by the EU is not driving up electricity costs nearly as much as some people are claiming. In fact, they may soon benefit from this change with lower electricity costs, while the US and Canada continue to rely on more expensive fossil fuels.

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Let’s clarify the misunderstandings and myths about providing humidity for plants.

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What Is Humidity?

Humidity is the amount of water in the air. When liquid water evaporates, it turns into a gas we call “water vapour”. Humidity measures the amount of water vapor in the air and can be expressed as both absolute humidity and relative humidity.

• Absolute Humidity: This describes the total amount of water in the air, regardless of temperature. It is expressed as grams per cubic meter (g/m^3).

• Relative Humidity (RH): This is the % you see in weather reports. It measures how close the air is to being saturated (full) of water. At 100%, the air is fully saturated with water.

Temperature affects the amount of water that air can hold. Warm air can hold more water vapor than cold air. Imagine the air as a sponge. A “warm” sponge is giant and can soak up a gallon of water. A “cold” sponge is tiny and can only hold a cup.

• If you have a cup of water in the giant warm sponge, the relative humidity is low (maybe 10%).

• If you take that same cup of water and squeeze it into the tiny cold sponge, the relative humidity is high (100%), and the sponge starts to leak.

This is why “Relative” humidity is so important. If the temperature drops at night but the amount of moisture stays the same, the relative humidity rises. When it hits 100%, we reach the Dew Point, and the water vapor condenses into liquid—forming dew, fog, or rain. This is why plants in your garden have droplets on them early in the morning, in spring and fall, when nights are cool.

How Does Humidity Affect Us?

Humidity dictates our comfort because of how it interacts with our body’s cooling system: sweating.

The metabolism in our bodies produces heat, and sweating is one way we get rid of this heat. It requires heat to convert liquid water to water vapor, thereby cooling us. When the humidity is high, the water won’t evaporate, we can’t cool ourselves, and we feel hot.

How Does Humidity Affect Plants?

Just like humans, plants “breathe” and regulate their temperature through moisture exchange. While we sweat, plants undergo a process called transpiration, where they release water vapor through tiny pores in their leaves called stomata.

Plants also have another reason for releasing water. They move water and nutrients from roots to leaves using the Xylem. Once in the leaves, the water needs to be expelled so that more water can move up from the roots.

When humidity levels are too high, water has difficulty evaporating through the stomata, stopping the whole process.

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The ideal humidity level for plants is around 50%, which is about the same as for humans.

Condensation on Windows

There is another reason for keeping humidity levels lower in winter. When humidity gets above 50%, water vapor condenses on cold windows in winter, which is not good for your home. To balance the condensation problem, with the needs of plants and myself, I try to keep our humidity at 45% to 50%.

Keeping Humidity High for Plants

During winter in cold climates, it is common to see humidity levels in the 10% to 20% range, which is too low for plants and can cause the following problems.

• Brown edges on leaves

• Wilting plants

• Leaves turning yellow

• Foliage dries out and becomes crispy

• Spider mites

The solution to these problems is to increase humidity, and gardeners have developed a number of solutions. Unfortunately, most don’t work very well.

Misting Plants

Misting does increase humidity around the plant. But for how long?

When the mist lands on the plant, it sits there as water droplets. Over time, this water evaporates into vapor and spreads throughout the room. Gases don’t stay put. Once the droplet is fully evaporated, the humidity around the plant quickly drops to the level of the whole room. A little misting does not change the humidity in a normal-sized room.

The time it takes to evaporate the droplets depends on the droplet size and the room humidity. It evaporates faster at low humidity. In a dry winter home, you will be lucky if it lasts 15 minutes. That means you need to mist every 15 minutes to keep the humidity high around the plant. Who is going to do that?

Misting can also cause fungal growth on some plants.

Unless you are growing some special plants like air plants, misting is a complete waste of time.

Pebble Trays

One of the most common recommendations for increasing humidity around plants is the pebble tray.

I learned this was a complete myth 40 years ago when I started growing orchids, but it is still promoted today.

Water does evaporate from the pebble tray and increases the humidity right above the water. Once the water is in the form of a gas (water vapor), it quickly moves away from the pebble tray, in all directions, by a process called ‘diffusion’. The water molecules spread out throughout the entire room, and if the door to the room is open, they spread throughout the whole house. The amount of water added to a room from a pebble tray is so small that it does not change the humidity of the room. The humidity a few inches above the pebble tray is the same as the whole room.

The same thing happens when you cook or have a shower. The humidity from the steam does not stay above the stove or in the shower. It quickly moves into the rest of the house. Long before dinner is over, the humidity above your stove has disappeared.

This change in humidity above a pebble tray was tested by an orchid enthusiast. The numbers he found for humidity increase above the try are displayed in the above image.

Increasing humidity by 1% or 2% at plant level has no significant effect on plants. Pebble trays don’t work.

The Baggy Method

This method is quite simple and does work well. You simply place the plant into a plastic baggy and seal it up. You would not put most plants in this situation, but it works well for some special cases.

• Leaf Cuttings: This is a great method for starting something like African violet leaves or Streptocarpus leaves that want 100% humidity until they root.

• Stem Cuttings: Standard softwood or semi-softwood cuttings are placed into soil and put into the bag for 100% humidity until they root. In this video, I’ll show you an even better method.

• Small Seeds: Very tiny seeds are normally sprinkled on top of the soil, and they need high humidity until they germinate. The baggy method is great for this. I use it all the time to germinate Streptocarpus seed as well as other small-seeded perennials.

Once the leaf roots or the seed germinates, you should open the bag to reduce humidity. I usually open it a bit, but keep it mostly closed for a few days. Then open it more for a few days. Then roll it down halfway for a while, and finally remove the bag completely.

I know this process slowly reduces the humidity, but I have never seen data to show how much it actually reduces. So I ran some tests.

A pot was filled with soil, it was watered, and placed in a closed baggy. Humidity was measured in the closed bag as well as at various stages of opening it. It was left for several hours at each stage to make sure the humidity reading had stabilized. The conditions in the room were: humidity 46%, temperature 22.9 C.

Closed baggy with some water sprayed into the bag using a hand mister. Humidity was 94%.

The open bag had a humidity of 78%.

Once the bag was open and the sides were rolled down about halfway, the humidity dropped to 55% over 24 hours. I then added a bit of water to the bottom of the bag, and the humidity was 66% by the next day. The moisture in the pot alone was not enough to keep the humidity significantly above the room's humidity.

Place Plants in a Humid Room

Bathrooms and kitchens tend to be a bit more humid, and some suggest placing plants there. How beneficial is this? Right after a shower, the bathroom is humid, but unless you close the door to trap that humidity, it soon dissipates into the rest of the home, and modern homes have a system for pulling out the humidity even if the door is closed. Kitchens are similar. They get humid around meal time, but they are dry the rest of the day.

This suggestion may work in some cases, but I suspect it makes little difference.

Crowded Plants Increase Humidity

Putting all your house plants in one spot can be effective. Each plant transpires water out of its leaves, creating a higher humidity layer around the leaves. When several plants are growing close together, they can generate enough water to keep the area more humid. Unless you have a lot of plants or a small room, this effect will be limited.

But even if this method does not work great, it is still a good reason to buy more plants :)

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What Are Microplastics?

Plastics are everywhere, and almost all of them slowly break apart into smaller and smaller bits of plastic. Large pieces are called garbage, but it breaks down into pieces so small our eyes can’t see them, we call them microplastics.

Microplastics are less than 0.2 inches (5 mm) in diameter. These pieces continue to break down even further until they become nonplastics. This process continues until they are fully gone, which can take many thousands of years.

Scientists have found these particles everywhere, including in our food, inside our bodies, and in the environment. That sounds scary, but so far we have not found any detrimental effects of these particles. The problem is that the number of them is increasing very rapidly, and at some point, they will probably cause problems.

A recent study found 300,000 pieces of microplastics per kilogram (2.2 lb) of food waste collected from grocery stores in the United States. Even bottled water contained 325 particles per liter.

Plants absorb nanoplastic particles into roots, and these have been found in the edible portion of food, with roots having higher levels than aboveground vegetables. Plastic particles can affect the properties of soil, including texture and structure, which in turn may impact plant performance.

One of the biggest sources of microplastics is the mechanical friction of car tires against the road, which sheds millions of tiny synthetic rubber particles into the air and runoff.

What Happens to Microplastics in the Environment?

As mentioned above, the particles naturally decompose and break into smaller and smaller particles. The actual mechanism and speed of this process depend on the plastic.

To give some insight into this, consider a fresh salad sold in a plastic clamshell. It sits there for a few days before you eat it, but by that time, pieces of plastic have broken off the packaging and are eaten along with the salad.

Microplastics in the environment are naturally broken down in a variety of ways.

Plastisphere: A New Delicacy for the Microbes?

Microbes naturally degrade plastic, but there is a significant catch. While many natural microbes (bacteria and fungi) have been discovered that can “eat” microplastics, they usually do so at a pace that is far too slow to keep up with global pollution.

In the natural environment, these microbes often form a “biofilm” on the plastic surface, creating a living layer known as the Plastisphere.

Researchers have identified over 800 microbial species—roughly half bacteria and half fungi—capable of breaking down synthetic polymers.

Microbes excrete digestive enzymes that break down plastic into small carbon-based molecules, which are then absorbed and used as an energy source. The carbon is eventually excreted as CO2.

This sounds great, but there are two major hurdles.

• The Speed Problem: In the wild, it can take decades or even centuries for natural microbes to fully degrade a single piece of microplastic.

• The Trojan Horse: The “Plastisphere” can actually be dangerous. These microbial layers often attract pathogens and antibiotic-resistant bacteria, essentially turning microplastics into floating rafts that transport diseases across the ocean.

Bacteria, fungi, and algae can all biodegrade plastics. Even plants play a role. Microplastics can accumulate in the rhizosphere (area around roots), effectively removing them from water that is flowing through the soil. Plants can also absorb nonplastics and pass them to the upper tissues of the plant, which can be removed and processed.

In the last couple of years, scientists have started to bioengineer microbes to perform better.

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Bioengineered Bacteria for Waste Treatment

Microplastics go right through wastewater treatment plants, so scientists are trying to develop engineered bacteria that degrade them right in the sewage treatment tanks.

Researchers from the University of Waterloo started with several species of bacteria that are naturally found in wastewater. They added special strands of DNA to them to make them more efficient at degrading polyethylene terephthalate (PET), a common plastic found in carpet, clothing, and containers for food and beverages.

The research group is using a special property of bacteria called conjugation, which allows bacteria to share DNA with each other. In simple terms, a donor cell with the special DNA is able to connect to another bacterial cell and transfer a copy of the DNA to it. Once the recipient has it, it can use the DNA to make special proteins for digesting microplastics.

In theory, this allows you to add a small number of modified bacteria to a wastewater tank and have the special DNA transfer to many existing bacteria already in the water. It “amplifies” the power of the initial bacteria, making the process more efficient.

Although the initial concept work is promising, the technology needs more testing before it can be implemented.

The Technical Details:

Conjugation is often called “bacterial mating,” though it’s technically Horizontal Gene Transfer (HGT) because it doesn’t create a new organism—it just upgrades an existing one.

The process is remarkably mechanical:

The Approach (Pilus Formation): The Donor cell grows a long, hair-like tube called a sex pilus. It acts like a grappling hook, reaching out until it attaches to a Recipient cell.

The Contact: The pilus retracts, pulling the two bacteria physically close together until their cell membranes touch and form a controlled opening (a conjugation bridge).

The Transfer: The Donor doesn’t give away its only copy of the plasmid. Instead, it “unzips” the double-stranded DNA plasmid and sends one single strand through the bridge to the Recipient.

The Replication: Both cells now have a single strand. They immediately synthesize a matching strand to make the DNA double-stranded again.

The Transformation: The Recipient is now officially an Donor. It has the new genetic traits and the ability to pass them on to the next “neighbor.

Sticky Algae Collects Microplastics

Cyanobacteria, also known as blue-green algae, are common in freshwater. These microbes are able to photosynthesize sunlight to produce their own food. Although they are called algae, they are really bacteria.

Genetically engineered cyanobacteria have been produced that may help reduce microplastics in freshwater and sewage treatment plants.

Microplastic particles are so small that it is very difficult and expensive to filter them out of water. Special cyanobacteria may solve this problem.

The DNA of these organisms has been altered so that they produce a lot of limonene, which is the same compound that gives oranges their orange-citrus smell. It is also found in cannabis. Limonene is not very water-soluble and sticks to the outside of the cyanobacteria, making them very sticky.

Microplastics are hydrophobic and stick well to limonene. When you mix the cyanobacteria and microplastics in water, they aggregate into large clumps of sticky material. As the clumps get larger, they also get heavier and gravity pulls them to the bottom, where they settle as sediment.

That sediment can be harvested and filtered out of the water, producing clean water.

This process can be done in smaller reactors or in ponds and settling tanks, similar to those found in waste treatment plants.

Natural Microbes Are Adapting to Plastic

In 2016, scientists found a bacterium that was able to biodegrade PET using an enzyme now called PETase. Further testing has found bacteria that produce this enzyme in 80% of our oceans, including both surface water and depths of nearly two kilometers.

It is believed that the bacteria are evolving to make better use of their new food source - plastic garbage. This might be of particular importance for microbes found in deep waters, where a carbon source can be scarce.

Is Plastic Pollution Solved?

Not by a long shot.

Most of the genetically modified bacteria speed up the biodegradation process by 10%, but it is still a slow process. Microbes can also be difficult to manage in large-scale processing. Their enzymes may be easier to use.

A French company named Carbios is building a processing plant that will use engineered enzymes to recycle PET plastic, the dominant polymer in bottles, food packaging, and polyester textiles. Carbios has optimised the enzyme and the process to deconstruct all types of PET waste into its basic components, which can then be shipped to plastic manufacturers to make recycled PET and then new products. The plant is scheduled to open in 2016.

Soon, your T-shirts might be made from the water bottle you used.

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It is a stretch to call CO2 a plant food, as it only contains one of the more than 20 nutrients plants need; however, carbon is one of their essential nutrients.

The increase of CO2 in the atmosphere is making plants grow better, but the benefits of this are overstated, and I’ll have a closer look at the pros and cons in the next article. The purpose of this article is to examine how plants are affected by CO2 fertilization, a term used to describe today’s higher atmospheric levels.

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How Does Elevated CO2 Affect Plants?

The CO₂ fertilization effect does more than increase photosynthesis, but that is a good place to start the discussion.

Photosynthesis and CO2

Plants carry out a chemical reaction called photosynthesis, which uses energy from the sun, water from the soil, and CO2 from the air to produce sugars and oxygen. The reaction is commonly expressed as:

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

This reaction is not correct, as I have outlined in Plants Don’t Produce Oxygen (O2) From Carbon Dioxide (CO2), but it is close enough for this discussion.

The sugar (C₆H₁₂O₆) that is produced is a form of energy that all living organisms use to carry out their metabolic reactions. When photosynthesis is ramped up due to extra CO2, the plant has more energy, which it uses to grow bigger and faster.

Photosynthetic Acclimation

So far in the discussion, higher levels of CO2 speed up photosynthesis, which produces more sugars and larger plants. But plants are not static organisms. They can adjust their metabolism to make the best use of the growing conditions.

Why run the photosynthetic machinery at full capacity when it doesn’t need to? Once a plant has access to more CO2, it stops making as much Rubisco and other photosynthetic proteins. This process is called photosynthetic acclimation or downregulation. The plant acclimates to the new conditions and slows down the photosynthesis process to produce the same amount of sugars that were being produced with lower CO2 levels.

One study reported that: “Within 3 weeks, plants maintained at elevated CO₂ exhibited a physiological adjustment of their photosynthetic rate so that plants grown at ambient and elevated CO₂ levels had similar photosynthetic rates.”

There is another factor that makes photosynthetic acclimation more likely.

As elevated CO2 speeds up the photosynthetic process, the plant needs more raw materials like water, nitrogen, and other nutrients. If these are not available, the plant can’t make use of the higher CO2 level, and the process slows down.

A study just published looked at historical tree rings and concluded that nitrogen will become the growth limiting factor. Even as CO2 continues to rise, trees won’t be able to use it.

This has been shown by numerous studies. For example, one study using a sweetgum forest stand in Tennessee with nitrogen limitation found that elevated CO2 increased growth in the first 6 years by 24%, which then declined to 9% in the following 5 years.

They concluded: “Global analyses that assume a sustained CO₂ fertilization effect are no longer supported by this FACE experiment.”

Plant growth is very sensitive to temperature and the higher temperatures caused by increased CO2 levels slow down plant growth, counteracting the increase from CO2.

The degree of photosynthetic acclimation is genetically dependent and is one reason to account for the fact that different cultivars of a species perform very differently with higher CO2 levels.

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Plants Use Less Water

The above reaction shows that for every carbon dioxide (CO₂) molecule, the plant uses one water (H₂O) molecule. It stands to reason that if it uses more CO2, it would need more water. That is true for this reaction, but water is used for much more than just photosynthesis.

One of the main uses of water is to carry nutrients from the soil to the leaves. Think of it as water flowing in a pipe. When the water reaches the leaf, the nutrients are absorbed into leaf cells, and the extra water is released through openings in the leaf called stomata.

These stomata are also used to access the CO2 in the air. When they are open, the plant absorbs CO2 and releases water at the same time. At higher CO2 levels, the stomata do not need to be open as much, and they close. This closure also conserves water.

The plant becomes more efficient in using water. The scientific term for this is enhanced “water-use efficiency” (WUE). Higher CO2 levels in the air allow plants to grow with less water, leaving more water in the soil.

It has been estimated that improved WUE from increased CO2 can increase soil moisture by about 11% on average, and up to 17% in drylands. This is one of the reasons why drylands have become greener over the last 30 years.

Deeper Root Growth

What happens underground with increased CO2 levels?

The improved above-ground growth allows the plant to shunt more sugars and other compounds to the roots, allowing them to increase growth.

This is not a great surprise. Plants try to maintain a balanced amount of vegetation both above and below ground. As one grows, so does the other. If, for example, the above-ground material is reduced by herbivory, the roots slow down their growth until the above-ground vegetation can grow and catch up to the root material.

Studies have shown that increased CO2 results in roots that increase in number, thickness, and depth.

This has several possible benefits.

• Access to Moisture: Deeper roots allow the plant to access deeper sources of water, mitigating the negative effects of increased evaporation from global warming. The downside is that deeper roots may remove deeper water sources and cause water tables to drop.

• Organic Matter: Deeper roots result in more organic matter deeper in the soil. More roots mean more root exudates being excreted from the roots (see mycorrhizal section below). Roots also die off on herbaceous plants and get regenerated. With deeper growing roots, this extra organic matter is also deposited deeper in the soil. It is still not clear what long-term effects this might have, but it might result in sequestered carbon lasting longer in soil.

• Microbial Populations: Increased organic matter will also increase microbial populations, which in turn increases total organic material in soil, resulting in improved soil structure. It may also alter the types of species and their number, which may or may not be a positive effect.

Cooling Effect of Plants

Water released through stomata has a significant cooling effect as the liquid water vaporizes into a gas. Extra plant growth has a cooling effect near the surface of the Earth, mitigating daytime and nighttime hot temperature extremes. A recent study estimates that this effect reduces hot temperature extremes by about 5%.

Another study reported that on average, greening has cooled the global surface by about 0.018°C per decade, which slows global warming by around 4.6%.

However, the effect varies by location and season. This cooling effect is much more substantial in some regions, like India and China, offsetting up to 39% of warming in India and 19% in China. These countries have warmer temperatures and have seen more greening.

Effect on Mycorrhizal Fungi

Arbuscular mycorrhizal fungi (AMF) are special fungi that make a symbiotic association with the roots of 80% of terrestrial plant families. The fungi insert part of their hyphae into the root of their host. The plants provide the fungi with sugars and other metabolites, while the fungi provide the plant with water and nutrients, especially phosphorus and nitrogen. The amount of such carbon transfer can be as high as 30% of the photosynthates produced by the plant.

A study looking at this found positive effects for eCO₂ (environmental level of CO2) on mycorrhizal-plant associations, such as increased colonization and increased hyphae biomass. In the case of Thymus vulgare (common thyme), the combination of mycorrhizal fungi and eCO2 produced growth with higher levels of sugars, organic acids, and amino acids.

However, other studies did not show any beneficial effects for eCO₂. The impact of eCO₂ levels on mycorrhizal growth seems to be dependent on plant species, fungal species, and soil type.

Increased mycorrhizal activity can increase carbon sequestration in soil, but some studies have suggested that it might also lead to increased soil carbon loss through accelerated decomposition.

C3 vs C4 Plants

C3 plants have a “design flaw” in Rubisco, the enzyme responsible for photosynthesis. C4 plants have evolved to fix the problem.

In all plants, the enzyme Rubisco is responsible for grabbing CO2 from the air to make sugar. However, Rubisco evolved billions of years ago when there was very little oxygen in the atmosphere. Consequently, it isn’t very good at distinguishing between CO2 and O2. About 25% of the time, it grabs O2 by mistake, making the process very inefficient.

C3 Plants

About 95% of Earth’s plant species (wheat, rice, soybeans, all trees, and most weeds) are C3 plants. They are called C3 because the first compound they produce in the photosynthesis process has three carbon atoms. Because their Rubisco is constantly grabbing oxygen by mistake, they benefit immensely from higher CO2. A higher CO2 concentration in the air means that they are more likely to grab CO2 rather than O2.

It is not all good news. When it gets hot, C3 plants close their pores (stomata) to save water. This traps oxygen (produced by photosynthesis) inside the leaf and keeps CO2 out, slowing photosynthesis. These plants struggle in the heat.

C4 Plants

C4 plants (maize, sugarcane, sorghum, many tropical grasses, and grasses used for grazing) evolved more recently and fixed the problem. They use an improved enzyme, PEP carboxylase, to grab CO2. It never accidentally grabs oxygen.

These plants also use an airtight chamber to concentrate CO2 to make photosynthesis more efficient.

Because C4 plants have an internal “turbocharger” that concentrates CO2, adding more to the atmosphere around the plant does not improve photosynthesis very much. They are already operating at near-maximum efficiency. It has been suggested that there is no benefit for these plants above 400 ppm CO2, and we are currently at 430 ppm.

Are Food Crops Less Nutritious?

A recent review of the effects of CO2 on plant nutrition reports: The positive ‘CO₂ fertilization’ effect on crop yield is complicated by a decrease in many nutrients. An analysis of 130 varieties of plants found that elevated CO₂ decreased the concentration of 25 important minerals by 8% on average. Increases in mineral concentration under eCO2 have rarely been observed.

Seeds saw a decrease of zinc (Zn) and iron (Fe) by 9.3 and 5.2%, respectively, in C3 grains and legumes. However, crop varieties varied greatly, indicating that the deficiency could be overcome by selection.

Total protein concentration decreased by 10–15% in elevated CO2 for barley, rice, wheat, soybean, and potato. Both vitamin B and carotenoid (a precursor of vitamin A) concentrations were also lower. Concentrations of phenolics and other carbon-based phytochemicals tend to increase.

Because C3 plants are more affected by CO2, they will also have a higher degree of nutrient dilution compared to C4 plants.

A number of mechanisms have been proposed to explain the drop in nutritional value, but none explain all the cases adequately.

The decrease in nutrition may seem significant, but such decreases also occur without a change in CO2. Differences in soil and available water also lead to deficiencies. Long-term FACE (free air CO2 enrichment) studies on grains found that soil conditions can be even more dramatic than the effects of CO2.

Higher levels of rainfall can result in significant increases in biomass and drops in protein.

Concentration vs Total Amount

The above paragraphs certainly imply that crops grown under high CO2 are less nutritious, but that statement is a bit misleading.

Here is a quote from above: “An analysis of 130 varieties of plants found that elevated CO₂ decreased the concentration of 25 important minerals by 8% on average”. Note the important word, “concentration”.

The statement is correct, and the method of reporting the information is valid. We tend to eat a certain amount of food, and reporting the nutritional level as a concentration in that food makes a lot of sense. But it does not paint a complete picture.

A study done at the University of Southern Queensland looked at protein levels in 19 different wheat genotypes. Pot plants were exposed to 311 ppm CO2 above ambient and produced an average increase in biomass of 48%. The amount of protein is shown in this chart:

The total amount of protein was higher in every variety except one. The concentration was decreased in some and increased in others. How can this be?

If a plant grows larger with excess CO2, it will have a larger biomass. Even if it holds more total protein, the amount per mass (concentration) may drop.

Impact on Human Nutrition

The decrease in Zn and Fe levels can have a significant impact in some parts of the world where there is already a known deficiency of these nutrients.

Increased Pests and Diseases

Plants produce a lot of defence chemicals that protect them from pests and diseases. When plants grow faster, they have fewer resources and time to produce these chemicals. This effect is very similar to the dilution of nutritious compounds.

Elevated CO2 results in more pest and disease damage.

Added CO2 in Greenhouses

Greenhouse crops can benefit from higher CO2 levels, and 1,000 ppm is routinely used for this purpose. Many people use this as evidence that higher levels are good for plants, but it is important to understand that greenhouses control other variables to make use of the higher CO2.

They control temperature, nutrients, and water to maximize the yield under the new CO2 conditions. Nature can’t do that, and agriculture is limited to meet such needs.

Greenhouses are closed systems, and if left alone, the growing plants can reduce the CO2 level to below 200 ppm, which is too low for plants. In part, CO2 is added to compensate for this effect.

Extra CO2 does increase yields in greenhouses by an average of 25% - 40%. Tomatoes, peppers, and cucumbers can be has high as 100%, while greens are around 25%.

Just like field-grown crops, these crops also suffer from the dilution effect. Mineral and protein levels decrease. Vitamin C and some antioxidants increase. Some fruit like tomatoes and strawberries, become sweeter due to increased sugar levels.

Greenhouses are artifical situation that are very tightly controlled. This type of data can’t be extrapolated to the real world.

Conclusion

Are elevated CO2 levels good for plants?

Most plants can take advantage of the extra CO2 and grow better with less water. The greening effect on the planet clearly shows that the area covered by plants is increasing. They are now able to use drylands, which they were unable to use before.

These positive effects are countered by negative ones, like increased pests and diseases.

The positive effects of CO2 may be limited and offer only a short-term benefit. As CO2 levels continue to increase, the positive effects of more efficient photosynthesis will lessen.

Increased root growth and expansion of fungal networks may increase organic matter in soil, which should improve soil structure. This would be a long-term benefit for plants, but it is a bit too early to know that this will actually happen. More research is needed.

Overall, increases in CO2 are beneficial to plants. However, it may not be beneficial for humans.

Decreases in nutrition are one problem. Increased pests and diseases on agricultural and ornamental plants are another issue.

Faster-growing plants may also reduce water reserves in some areas, leading to future droughts.

Overall, increased CO2 has short-term benefits for plants, but it will probably be seen as a negative effect when levels get higher.

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The deniers don’t believe in global warming, so the cold polar vortex is their new proof that they are right.

The climate alarmists say that the cold polar vortex is the result of extreme warming in the Arctic and proof of climate change.

Both groups embrace the cold weather because it supports their beliefs. Who’s right?

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Is 2026 Unusually Cold?

“Southern Ontario is in the midst of its most persistent cold stretches in more than a decade, with the region pushing more than 16 days of consecutive, below-freezing temperatures. It is a run not seen since the historic winter of 2014-15.” The quote is dated February 2026, The Weather Network.

“The blast of cold that fueled record snowfall across Gulf Coast beaches last week was just the latest to transport frigid air that normally swirls above the North Pole to places much farther south”. Quote is dated January 30, 2025, The Washington Post.

“In mid-January, we experienced a period of extreme cold, high winds, and a couple of inches of snow”. Quote dated February 7, 2024, Rutgers.

“In late February, as the Southern Plains and Gulf Coast suffered through an unusually strong blast of wintry weather, weather talk turned to the polar vortex and the possibility that the extreme cold was yet another example of weather-gone-wild due to global warming”. The quote is dated March 5, 2021, NOAA.

“It was the coldest winter storm for Texas since December 1989.” Quote dated February 2021, NOAA.

These are just a few of the recent claims. You can see that we incorrectly blame each year as the “coldest” year ever.

How cold is 2026?

Toronto: The number of Consecutive days at or below 0°C is now 16, but the record is 2015, which had 37 straight days.

Ottawa: It is also at 16 days, but that is nothing compared to the record of 61 days in the winter of 1944 & 1945.

We have experienced a cold vortex this year in Eastern North America, but it is not that unusual.

What is a Polar Vortex?

The cold air at the poles is controlled by the polar jet stream and polar vortex. These are two rings of fast-moving air around the Arctic and Antarctic, which play a large role in world weather patterns.

NOAA describes it this way: “The Arctic polar vortex is a band of strong westerly winds that forms in the stratosphere between about 10 and 30 miles (16-48 km) above the North Pole every winter. The winds enclose a large pool of extremely cold air. (There is an even stronger polar vortex in the Southern Hemisphere stratosphere in its winter.) The stronger the winds, the more the air inside is isolated from warmer latitudes, and the colder it gets.”

The polar jet stream is a moving air system between the cold polar air and warmer mid-latitude air and occurs in the troposphere at altitudes of 5-9 miles (8-14 km).

When the polar vortex is strong and stable (the left globe) it holds the jet stream farther north. Every other year or so, the polar vortex weakens and becomes less stable (right globe). When this happens, the jet stream brings colder air farther south in the Northern Hemisphere. The same happens with the Antarctic polar vortex.

NOAA admits that the interactions between the polar vortex and jet stream are “not fully understood”.

Climate change affects these systems because different parts of the planet are warming at different rates. In particular, the Arctic is warming twice as fast as the rest of the world. This warming means that the temperature difference between the Arctic and mid-latitudes is getting smaller, making the polar jet stream slower and weaker. That means it is more likely to bend north and south, and in effect, allowing the polar vortex out of its cage, which then drifts down into the mid-latitudes, bringing very cold weather with it.

As the polar vortex moves further south in one place, it usually moves more northerly in an adjacent area. As eastern North America is freezing in the winter of 2026, the western part of North America is experiencing unusual warmth. Vancouver, BC, is on pace for the warmest winter on record.

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Is the Earth Colder this Winter?

The Arctic is warming more than twice as quickly as the global surface average. In part, this stems from the rapid loss of sea ice cover in the region. As Arctic sea ice diminishes, energy from the sun that would have been reflected away by the bright white ice is instead absorbed by the ocean, causing further warming.

The Arctic sea ice extent has been stable since 2007. For details, see my post about polar bear populations.

January 2026 was the fifth-warmest January globally. During the second half of January 2026, severe cold conditions affected large parts of the Northern Hemisphere, including North America, Europe , and Siberia, mainly driven by a wavier-than-usual polar jet stream that allowed frigid Arctic air to spill into mid-latitudes.

Although some areas were colder than usual, most of the globe was warmer.

Does Global Warming Affect the Polar Vortex?

Many people are claiming that global warming is causing the unusual polar vortex behavior. Is this true?

Keep in mind that the so-called “unusual polar vortex” behavior this year is not all that unusual, as I have shown above. NOAA has reported that a weaker polar vortex happens every couple of years.

The polar vortex may prefer to be located in regions that are sensitive to sea ice cover. One study linked lower-than-average sea ice extent in the eastern Arctic’s Barents and Kara Seas to a shift in the polar vortex, resulting in colder-than-average winters across Siberia and the mid-latitudes of central Eurasia.

Analysis of climate models has shown the link to sea ice, but other models have shown no such link.

A good discussion of the theories and debate about them is available from carbonbrief.org, dated 2019, in which Jennifer Francis’s research in the matter led her to conclude, “Where the uncertainty still exists is in determining, for any given extreme event, how much of it can be attributed to effects of Arctic warming, other factors, or just random chance.”

NOAA concludes that scientists are still undecided about the role of global warming on the polar vortex.

We can’t blame the 2026 polar vortex on global warming. It is neither causing the cold weather, nor is the presence of cold weather a sign that the Earth is not warming.

Two Opposing Views

I started this post with two opposing views - which one is correct?

1. The deniers don’t believe in global warming, so the cold polar vortex is their new proof that they are right.

Clearly, the cold winter of 2026 and the polar vortex do not disprove global warming. Remember that even though some areas are cooler, the majority of the Earth is warmer. The evidence for global warming is very strong and does not support the view of this group.

2. The climate alarmists say that the cold polar vortex is the result of extreme warming in the Arctic and is proof of climate change.

This claim is possible, but the scientific community is still debating the hypothesis. At this point in time, this is not a valid argument supported by science.

Neither view is correct. 2026 is just evidence of weather variability.

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However, a closer look at modern agricultural logistics, the chemistry of nutrient degradation, and the speed of industrial flash-freezing suggests that our “fresh” vegetables are often older than we think, and our frozen vegetables are “fresher” than we give them credit for.

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The Illusion of “Fresh”

When we buy a head of broccoli or a bag of carrots labeled “fresh,” we imagine it was pulled from the dirt just yesterday. In reality, the journey from farm to fork is often a long and arduous process.

• The Transit Gap: Most produce in North America or Europe travels an average of 1,500 miles. The grapes I bought in Canada last week came from S. Africa.

• The Storage Life: Vegetables like carrots can be kept in cold storage for weeks or even months before reaching the shelf.

• The Retail Stall: Once at the grocery store, produce may sit under fluorescent lights for several days, losing moisture and nutrients with every passing hour.

During this time, the plant continues to “breathe” through a process called respiration. It consumes its own stored sugars and antioxidants to stay alive. By the time that “fresh” spinach reaches your pan, it may have lost up to 50% of its Vitamin C and folate compared to the day it was harvested.

That 1,500-mile “transit gap” typically translates to 7 to 14 days before the vegetable ever reaches your kitchen. Why does it take so long?

• Harvesting & Cooling: Most produce must be “pre-cooled” to remove field heat, which prevents immediate wilting.

• Sorting & Packing: Vegetables are graded, washed, and boxed.

• Consolidation: Farmers rarely ship a single truck directly to a single store. Produce usually goes to a regional cooling facility or a wholesaler first.

• The Journey: The 1,500 miles can take 2 to 4 days.

• The DC (Distribution Center): The truck unloads at a massive grocery chain warehouse. The produce may sit here for 24–48 hours before being sorted onto a smaller truck for a specific store.

• Store Arrival: Once at the store, it might sit in the “back room” cooler for a day or two before being stocked.

• Shelf Time: Depending on the store’s foot traffic, that “fresh” head of broccoli might sit on the shelf for another 2–3 days before you buy it.

When vegetables are imported from across the globe, they are often harvested before they are fully ripe to ensure they don’t rot during transport. Since many nutrients develop during the final stages of ripening on the vine, these vegetables start at a nutritional disadvantage.

The Science of Flash Freezing

Frozen vegetables undergo a radically different process. Most commercial vegetables are processed within hours of harvest—a window of time so narrow that the nutrients are essentially “locked in” at their peak.

• The Blanching Factor: Before freezing, most vegetables (like peas and carrots) undergo blanching. This involves a brief dip in boiling water or steam to denature enzymes that cause browning and off-flavors. While this causes a minor loss of water-soluble vitamins (like Vitamin C and B-complex), it stabilizes the vegetable for long-term storage.

• Ice Crystal Management: Modern industrial freezing uses “flash-freezing”. By dropping the temperature to below -18°C almost instantly, the water inside the vegetable cells doesn’t have time to form large, jagged ice crystals. This prevents the “mushy” texture often associated with slow-frozen home goods and preserves the structural integrity of the nutrients.

Heat treatment through blanching can increase the bioavailability of antioxidants and other beneficial phytonutrients. A study looking at tomatoes found that the antioxidant activity of raw tomatoes was 4.13, which increased to 6.70 with 30 minutes of heat treatment.

Case Study 1: The Humble Pea

The pea is the poster child for the frozen-is-better argument. Because peas are high in sugar, they begin converting those sugars into starch the moment they are picked.

• Vitamin C: Fresh can have lost 30% by the time you buy it. Frozen preserves almost all of it.

• Sugar Content: Sugar starts turning to starch as soon as picked. Freezing preserves the sugar and sweetness of the peas.

• Texture: Fresh becomes mealy tasting, while frozen keeps its “pop”.

A study from the University of Georgia found that frozen peas actually had higher levels of Vitamin A than their fresh counterparts that had been stored in a refrigerator for five days. Because peas are frozen within roughly 2.5 hours of being picked, they are nutritionally superior to “fresh” peas that have spent days in a shipping container.

Case Study 2: The Resilient Carrot

Carrots offer a slightly different perspective. Unlike peas, carrots are hardy. They have a thicker cell wall and a lower respiration rate, meaning they hold onto their nutrients longer.

• Beta-Carotene: Interestingly, some studies suggest that the heat from blanching and the freezing process actually makes the beta-carotene (the precursor to Vitamin A) in carrots more bioavailable. The process breaks down the tough cellular walls, making it easier for the human body to extract the nutrient.

• Imported vs. Local: A carrot imported from Mexico to Canada during the winter may lose some of its crispness and Vitamin C during the journey. A carrot frozen at its peak in the summer will maintain its nutrient profile for up to a year.

A frozen locally grown vegetable is better for your economy than an imported fresh one. Less shipping also means less damage to the environment.

Less Food Waste

Beyond pure nutrition, the “fresh vs. frozen” debate touches on food waste. Fresh produce is highly perishable; billions of pounds of fresh vegetables are thrown away every year because they wilt before they can be eaten. This happens both in the supply chain and in your home. Frozen vegetables have a shelf life of 8 to 12 months, drastically reducing food waste.

Furthermore, frozen vegetables are almost always cheaper and pre-prepped (washed and chopped), which lowers the barrier to entry for a healthy diet.

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Nutrition is More Than Numbers

We talk about nutrition in terms of the amount of a special chemical in food, but just as important is how much of the food you eat.

Take peas, for example. Shelling peas is a lot of work, and it’s the reason I don’t buy them fresh. In the garden, I grow sugar snaps that don’t need to be shelled. Frozen peas are already peeled and much easier to use. Just drop a handful into any soup or stew.

That means I eat more peas. So even if the nutrition of frozen peas were lower, I actually get more nutrient compounds from frozen peas because I eat more of them.

Final Verdict

The “best” vegetable is the one you actually eat. However, the data is clear: the gap between fresh and frozen is negligible for some vegetables and favors frozen for others (like peas and spinach).

Your best option is your own garden or a local farmer. However, if you are shopping at the supermarket, frozen is a second-best option.

While fresh vegetables offer a superior crunch for salads and raw snacks, frozen vegetables are the unsung heroes of the nutritional world. They bypass the degradation of long-haul shipping and the nutrient-leaching effects of the grocery store shelf.

Next time you’re in the store, don’t walk past the freezer. You aren’t buying “lesser” food; you’re buying a nutritional snapshot of a vegetable at its absolute best.

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