What is Biochar & Why Use It?

Using biochar is an ancient tradition that spans back over two thousand years. The basic principal is that biomass is carbonised and then added to the soil to improve the soil quality, sequester the carbon in the ground and prevent the nutrients from being washed away with the rain.


Thank you to Red Garner for the image.

How is it made? Agricultural waste can be burned in a way that uses little or no oxygen, and the result is very similar to charcoal. Not all charcoal would be good for use as a soil enhancer, however, as much of the mass produced charcoal has additives and chemicals that would not be conducive to organic food production.

Where farmlands and soils that produce our foods have been severely depleted with single crops and over use of that land- not allowing it to rest or rotating the crops- biochar can significantly improve the quality of the soil. It also can help to retain water where water resources are scarce.

There seem to be debates about how much to use, or how often to use it, but this is because more research is needed on the subject. However, what is clear is that we are a planet in trouble, and this could well be part of the solution to help combat climate change.

In areas where water is not plentiful, treated biochar can help to maintain the water levels of the soil, as the carbon can absorb and retain the water. It is also thought to maintain its structure and not degrade for many centuries.

How can Biochar help to combat climate change? It is obviously not the answer to climate change, but where it can be effective is in sequestering the carbon into the soil. It reduces greenhouse gases by storing carbon in this stable form. When we put biochar into the soil along with other plant matter, it is said to remain in the same form for hundreds of thousands of years. This prevents the gases from being released into the air as carbon dioxide, which would have happened if the plants had decomposed. So the biochar becomes carbon negative, and helps to reduce global warming.

As part of the project, we are going to make biochar from the “waste” products of the forest. The soil in Africa is dry and compact, and so it is important to feed it and ensure that water saving practices are followed. It will be important to feed the trees for the first 4 years of their lives as after this point, they are able to get their nutrients and water supplies through their roots.

Biochar is a subject that we will be learning about and implementing for this project as it can help with soil improvement, water retention and enabling us to be carbon neutral.

The Tree Planting Team!