I literally just came home today from Hawaii, where I've been living and working (for wages) on an organic tea farm on the Big Island. I spent a month there with a Mad Farmer who swore by a method of agriculture involving 'Bio-Char': literally using fine-sifted charcoal for soil amendment. He swore by the stuff.
It's known as "terra preta" in Spanish, because vast deposits of this "black earth" have been found in the Amazon, clearly anthropogenic in origin, and these are considered the factual base for the myths of mighty civilizations reported to have existed during the Age of Discovery by hallucinogenic starving feverish Spanish explorers in the sixteenth century. Contemporary studies have found terra preta to be extremely fertile soil which is a stark difference with typical rainforest soil, which is nutrient-poor muck by nature and incapable of supporting intensive agriculture.
As I understand it, the activated charcoal provides a habitat for the critically important microorganisms who break down the nutrients in soil and mineral bits and make them available for the plant roots. When combined with a microbe-rich substance (manure, IMO, or any other kind of stinky rotting matter) the mix becomes some kind of super-fertilizer that makes plants extremely happy. He was a scientist by disposition, and conducted experiments on his property that proved conclusively that the use of this bio-char increased yields by an extraordinary degree.
So every other day we were filling a 4 x 5 x 3 foot fire-brick lined pit with wood and burning it for charcoal to fertilize his fields. It was an interesting little experience.
He actually sells the stuff for a profit (only because he has his own timber supply on his property). He did some calculations and found he could make about $35/hour just by burning firewood and sifting the end product to sell as patent bio-char.
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Topic: Gardening... Stuff you grow for food thread. (Read 5820 times)