Biochar – what’s the deal?

Fri. Jul. 17, 2020

Click below to listen to my 2 min. Garden Bite radio show: Biochar – what’s the deal?

On a tour of local gardens years ago, there was a standout. It was all about vegetable gardening. “John” has been gardening a long time and when I stepped into his backyard I was astounded at the size and beauty of his produce!

John’s place!

His secret is all in the soil, or will be. He makes his own biochar.  It’s NOT ASH.

biochar from U of MN

Basically, it’s organic matter, he uses wood that is burned slowly, with a restricted flow of oxygen, and then the fire is stopped when the material reaches the charcoal stage.

Unlike tiny tidbits of ash, coarse lumps of charcoal are full of crevices and holes, which help them serve as life rafts to soil microorganisms. The carbon compounds in charcoal form loose chemical bonds with soluble plant nutrients so they are not as readily washed away by rain and irrigation.

John’s amazing vegetable gardens

Biochar alone added to poor soil has little benefit to plants, but when used in combination with compost and organic fertilizers, it can dramatically improve plant growth while helping retain nutrients in the soil.

One method of making biochar is to pile up woody debris in a shallow pit in a garden bed; burn the brush until the smoke thins; damp down the fire with a one-inch soil covering; let the brush smolder until it is charred; put the fire out. The leftover charcoal will improve soil by improving nutrient availability and retention.  It stays in the soil for millennia and is found all around the world.


How to Make biochar by New Farmers Almanac

Biochar and Reclaiming Urban soils by Nakano Associates

Your biochar questions, Answered by Green Infrastructure

Not everyone agrees that biochar is a good thing.  Read on for more:

Beward the Biochar initiative – Permaculture Research Institute

There are a lot of videos on how to make it, please be aware of the source of these videos and find out how reputable they are!  Here’s one I felt was responsible…