The Amazon natives created a self-sustaining soil that was very fertile,and actually grew in depth every year.Amazon soil is actually very poor in nutrients,and depletes very rapidly.The native Indians developed a way to make the soil fertile.
It is a dark black soil called Terra-Petra.
It consisted of waste products,like fish bones, animal bones,broken unglazed pottery,bio char and clay.The porous nature of the charcoal,unglazed pottery,bones,clay,and vegetable matter, animal,and human waste a have a lot of surface and internal area for micro biomass inhabitants to flourish.
Scientists are trying to duplicate it to reduce dependence on fertilizers and help to preserve the rain forest because the soil replenishes itself.
Normally,the forests are cleared,planted, and in a few years the soil is depleted of nutrients and another parcel of forest is cleared.
Bio char is a good,but incomplete soil complement.
I have built up my soil with a combination of bio char,crushed oyster shells,crushed brick(unglazed pottery). It is as close as I can get to Terra Preta,and it is amazing the difference it makes.I also added a batch of Earthworms to aerate the soil and add phosphate by their droppings.
The topsoil actually gets deeper every year as the organisms work their way down.
I am still working on the exact ratio of the ingredients,but if anyone is an organic gardener they might want to try it for themselves I am sure the mixture ratios will vary according to local soil conditions.
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