Soil Building 201: Biochar

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Garden Tower Project > Gardening > Soil Building 201: Biochar

Biochar is a immensely valuable soil amendment. According to the International Biochar Initiative, “This two thousand year old practice converts agricultural waste into a soil enhancer that can hold carbon, boost food security, and increase soil biodiversity, and discourage deforestation. The process creates a fine-grained, highly porous charcoal that helps soils retain nutrients and water.”

Biochar is easy to make.
Biochar is easy to make.

Biochar is a charcoal made at low temperature which is then inoculated with beneficial bacteria and soil organisms that inhabit the porous and expansive surface areas. Because nutrients, beneficial soil organisms, and water are all held by the biochar and slowly released, soils are greatly improved, and maintain their fertility, over a long period of time. These were first found as terra preta in the Amazon, where they miraculously held fertility in tropical soils. Biochar is useful when incorporated into temperate soils as well.

Biochar is now used agriculturally, both to build fertility in the soil and for animal feed and overall health. Biochar is able to capture and purge harmful bacteria in the digestive systems of many domesticated farm animals. As a feed additive, it is very useful. A 2012 report stated that 90% of European biochar was used in livestock farming. Health food stores stock activated charcoal on the shelves in order to help deal with digestive issues. Feeding biochar to livestock is right in line with this practice.

In addition, biochar can help address climate change by storing stable carbon in the soil for hundreds of years. While there are many ways, such as rotational grazing, to build carbon in the soil and remove it from the atmosphere, biochar can be an important aspect of addressing climate change while providing systemic terrestrial system benefits.

What Can Biochar Do For You?

It’s easy to incorporate biochar into your garden soils. Consider using it as a feed additive for your livestock. Learn to make it yourself and encourage others to make it and provide it as a product in the community. Be aware that any time you introduce bacteria and new components into an ecosystem, you should know what you are incorporating and how to observe the space to note impact.

If you consider biochar as a possible remedy for excessive carbon dioxide in the atmosphere, it might be tempting to think that cutting down trees and creating biochar is the solution. We now know that we need our large trees and established forests to do what they do best. Trees provide oxygen and support many other vital ecosystem services. What we need now are new forests and new ways of working with agroforestry. Then, we can produce new biochar in these areas.