Horticultural charcoal is becoming an increasingly common soil amendment, but when it comes to healing sick toxic soils, activated charcoal is the treatment of choice. The term horticultural charcoal is a spinoff of the biochar revolution that also popularized the use of plain charcoal in agricultural management. Studies of ancient man-made soils [Terra Preta] in the Amazon basin showed the impressive benefits of incorporating plain charcoal in otherwise low productive soils. These vast areas of man-made soils using charcoal made in simple ovens/kilns boasted up to 400% increased fertility over nearby similar soils without charcoal.
These studies in the Amazon jungles helped to spearhead the “bio-” movement which has segmented into bio-mass, bio-fuels, bio-degradable, bio-reactors, biomes… and bio-char. Biochar, used specifically for agriculture, has gone through a couple name changes, agri-char… and now horticultural charcoal. Clearly, horticultural charcoal is wise soil management for otherwise uncontaminated ancient jungle soils and unpolluted modern gardens and farms. But today, the reality is most soils that have been under cultivation for any time at all are contaminated and polluted with any number of manmade chemicals with their toxic residues. This is where activated charcoal for plants, lawns, golf greens, excels over horticultural charcoal.
There is a saying among activated charcoal/carbon producers and developers that goes, “A thousand applications today, a thousand and one tomorrow.” There are easily 200+ distinct grades of activated charcoal, as well as dozens of biochars. Each performs optimally for specific applications, whether it’s for air and water purification, health and beauty, military and aerospace, pharmaceutical, nutraceutical, animal husbandry… or agriculture. When it comes to treating poisoned soils, activated charcoal for plants is superior to horticultural charcoal.
Emergency Care
For sick and toxic soils, there are well-defined applications. Some charcoals work very well, others have no positive benefits. When a person is admitted to a hospital (i.e. for poisoning), that person receives intensive emergency care (most often coconut activated charcoal). Rehabilitation care comes after the person is stabilized. The same is true for sick soils. If the goal is to revive otherwise dying or dead soils, and eventually convert over to “organic” farming methods, emergency care should be uppermost on one’s game plan. Whether it’s plowing up an old, abandoned backyard garden or a quarter section of commercial pineapple plantation, if the soils have been exposed to prolonged use (light OR heavy) of inorganic chemical fertilizers, herbicides, pesticides, fungicides… then activated charcoal should be the first response.
“Organic Carrots”
How effective can the right kind of activated charcoal be in neutralizing the buildup of soil toxins from commercial chemical land management? A couple years after we started our business, I was looking into purchasing activated charcoal for toxic soil management from one of the largest activated charcoal manufacturers in America. In the course of my conversation with the sales representative, she told me their product was widely used in agribusiness.
“What for?” I asked.
“Well, for example, for a large crop of ‘organic’ carrots.”
“How so?”
“The grower, after cultivating the area, sprays on a total herbicide like Agent Orange that kills everything in days. After 7-10 days, he comes back and treats that entire field with our brand name activated charcoal for plants and seeds a crop of ‘organic carrots.’ That activated charcoal works so quickly and extensively that the trace amounts of the herbicide are negligible!”
Whether that was mostly sales hype or not, the reality is, the right kind of activated charcoal can, in fact, work just as fast in a toxic backyard garden or field as one does in poisoned children or adults in the emergency ward.
Now, one has to understand that even with these amazing results, once a human body or the earth has been exposed to these lethal chemical drugs, they never completely lose the toxic effects. There is the ancient biblical saying, “As a man soweth, so shall he reap.” The wise man observed that having introduced a noxious seed (physical or spiritual), that piece of land/mind will never completely lose the baleful influence. It’s a sorry comment that having exploited the earth with the burning, addicting properties of man’s short-sighted chemistry, those soils will never wholly regain their virgin purity. BUT, there is reason for courage and faith.
Activated charcoal is known to adsorb thousands of plant-based and manmade toxins from sick people, sick animals, sick air and water, and from sick soils. The degree to which activated charcoal can work quickly in binding and neutering those poisons has much to do with how much surface area it has. It’s obvious that the greater the binding surface of a remedial agent, the more toxin can be quickly adsorbed to that surface. A hospital grade activated charcoal used for accidental poisoning or in a kidney dialysis unit has a minimum internal surface area of 1200 sq. meters per gram. If we could magically unfold all that internal surface area, it would compare to the size of a soccer field. A quality activated charcoal for soil remediation can have upwards of 1500 m2/g of internal surface area. A quality horticultural charcoal/biochar may only have 340 m2/g. It isn’t difficult to see, when it comes to adding charcoal to soil for emergency care, that activated charcoals can work much more rapidly and broadly than even the best horticultural charcoal.
Activated Carbon Made from Coal
For decades, industry relied on activated carbons made primarily from coals. Industrially, by definition, an activated carbon is made from a non-renewable source like coal or petroleum resins. An activated charcoal is made from a renewable source like coconut shells, rice hulls, bamboo, corn stover, or even Everglades grasses. Except for the technical differences, both are effective detoxifiers of poisoned soils. But “coal” has earned a ‘dirty’ characterization, while renewable charcoals have gained a ‘cleaner’ advantage.
Here are some bioremediation examples of using activated charcoal for contaminated soil.
Poinsettias
Some years ago, we received a frantic call from a large commercial poinsettia nursery. Their entire crop was drooping and dying. A popular pre-emergent, at 20 times the recommended concentration, had been applied in one section of the greenhouses and had been airborne to the rest of the nursery. We overnighted two sacks of our Soil D•Tox™ which was applied to the affected areas. Just two days later, we received a call from the manager who was thrilled at how effective the initial results had been. They purchased an additional two sacks for follow-up treatment. After a few weeks, we received an update stating that they were able to move the plants back into their greenhouses shortly afterward.
Neutralize Pre-emergent in Nursery Stock
A charcoal slurry can be made by adding a few cups of activated charcoal powder to a bucket of water. When transplanting the plants, dip the roots, soil and all, into the slurry. Most herbicide, turf builder, pesticide, and weed killer will be completely neutralized with this method.
Rye Grass Seed Industry
Activated carbon made from select coal was, for years, a favorite treatment protocol for neutralizing pre-emergent and improving seed germination by the rye grass seed industry. In the last decade, activated charcoals for plants made from hardwood have become the favorite. Field trials by Oregon State University have shown wood-based activated charcoal to be much superior — 25lbs/acre (plus N & P 40 gal/acre) instead of more than twice as much coal-based AC. Plus, it stays in suspension longer in the venturi tanks during soil injection.
How to Neutralize Juglone
Juglone is the toxin produced by black walnut trees which occurs naturally in all parts of the tree, especially in the buds, nut hulls, and roots. Agricultural activated charcoal can effectively treat the areas around these living walnut trees. Where the trees have been cut down, the toxins can remain in the soil for years and the area should be treated at a rate of 1 pound mixed into 1 gallon of water for 150 ft2. The powder can also be spread directly on the area and watered in, but remember it is black and messy. Do not apply dry on a windy day.
Agricultural activated charcoal is also widely used on large areas by golf courses, along train track right of ways, by Depts. of Transport, and tractor farms to mitigate the effects of chemical spills or over application of herbicides. In most applications, the area can be seeded 24 hours after treatment.
Poisoned Pineapple Plantation
We were contacted by a large chemical company who owned a large pineapple plantation in Hawaii. They had used a potent herbicide to control weed growth between the planting rows and along the edges of the fields. The destruction was general. Their research pointed to the application of activated charcoal for agricultural use. They ordered about 238,000 lbs, and were able to begin replanting within two weeks.
Rehabilitation Care
Once you have turned over the years-old abandoned garden or plowed and harrowed an old tobacco field, now is the time to apply activated charcoal for plants. For small gardens or areas that have a history of chemical gardening, an application rate of 1 pound of activated agricultural charcoal stirred slowly into 1 gallon of water will effectively treat 150 ft2. Since the charcoal powder does not dissolve in water, agitate occasionally to keep charcoal suspended. This simple mixture can be applied when replanting ornamentals, turf grass, or food crops, flower beds, around fruit trees, or putting greens where herbicides have been previously applied.
Once emergency care is taken care of, one can now look to long-term rehabilitation care and the use of biochars including horticultural charcoal. According to the National Gardening Bureau, 7+ million more households are planning to grow some of their own food – over 20% increase post-pandemic. Whether it’s horticultural charcoal or agricultural activated charcoal for plants, charcoal is the green of the green, not only cutting CO2 emissions, but actually sequestering vital carbon back into carbon-depleted soils. The perfect win, win, win!
Where to Buy Activated Charcoal for Plants
Garden centers, big box stores, and websites sell horticultural charcoal in smaller bags. But for larger gardens, multiple bags can mean higher costs due to packaging, shipping, and portion sizes. For larger applications or to choose between agricultural activated charcoal for plants and horticultural charcoal, and biochar potting mix, choose a company that retails activated charcoal in bulk, such as Charcoal House.
John Dinsley is the author of “CharcoalRemedies.com The Complete Handbook of Medicinal Charcoal & Its Applications” [2005]. He and his wife Kimberly are owners of Charcoal House. Together they travel domestically and internationally conducting workshops on the prevention and treatment of common diseases using simple natural remedies.
© 2023 John Dinsley
