Meet Joany Grima. We were introduced through the biochar community — a network of people quietly doing big, practical things for the planet — and it quickly became clear she was one of the right people to help unpack a deceptively simple idea: turning Kowtow organic cotton clothing into biochar, to lock carbon into the earth to support biodiversity and regeneration.
Below, Joany answers your questions on biochar — what it is, how it’s made, and how organic cotton can be transformed into carbon-rich material that returns to the earth.
In your words Joany, what is biochar?
A simple explanation for biochar is that it's a kind of charcoal that safely stores carbon for a really long time. The main differences between biochar and charcoal is how they’re used. Charcoal is generally used for cooking or heating, while biochar is intentionally prepared to be safely used to improve soil health, and also to sequester carbon.
How is biochar made?
The term for the process of making biochar is called pyrolysis, which separates the carbon and minerals in the biomass (or in this instance, the clothing) from the other elements it contains, leaving behind mostly solid carbon. Pyrolysis is baking or cooking biomass in a low oxygen environment.
How is converting organic clothing to biochar different from composting them?
When we compost organic clothing, it eventually breaks down in the environment and becomes part of the soil. During the composting process, the carbon contained in the clothing is consumed by soil microorganisms and can readily be re-released into the atmosphere. Converting clothing into biochar locks in the carbon that would otherwise have been re-released into the environment, had the clothing been composted or allowed to naturally decompose.
How does biochar lock carbon in instead of releasing it?
Biochar locks in carbon because soil microbes can’t easily eat it or or break it down, so it doesn’t rot or turn back into CO₂ like normal plant matter would. The carbon can stay locked away for a really long time.
How does biochar help the soil?
Soil works really hard, and has no control over what goes on in the environment. As well as increasing carbon in the soil - which plants quite like - biochar contributes to making soil resilient. It helps soil hold water better, which is great for plants experiencing periods of hot weather; it provides a home for bacteria and fungi that live underground; and it helps to improve air flow and drainage, making the soil a more comfortable place for plants to grow and thrive in.
How does converting cotton clothing to biochar compare to sending them to landfill?
Sending cotton clothing to landfill makes no positive contribution to the environment. The clothing takes up landfill space, and the carbon contained in the fabric will eventually be released into the atmosphere.
Tell us more about The Good Carbon Farm and the work you do.
The Good Carbon Farm is a New Zealand-based not-for-profit, and we’re taking tangible climate action by providing free biochar to school and community gardens around the country.
Our biochar is upcycled from plant waste that would otherwise be left to rot and re-emit carbon into the atmosphere, and it’s made by a network of people we call our carbon farmers.
The Good Carbon Farm model is simple and circular: we take something that would otherwise go to waste, convert it into something useful, and put it back into the ground, for good.
The school and community gardens incorporate our biochar into their composting systems and food growing beds, which we like to think of as the opposite of mining because returning natural resources into the earth, rather than extracting them.
