May 16th. Demonstration of biochar making?

The United Nations has declared 2015 as the international year of soils. To recognize this fact, the Central Goldfields Sustainability Group organised a biochar making demonstration. This took place at Helmut Weber’s property at Daisy Hill. Helmut wanted to improve the local acidic clay for use in his garden and so built a biochar maker from a flue, a 44 gallon drum. some mesh, a steel grate and an outdoor heater reflector.. A second goal was to remove the fire hazard represented by leaf litter on his property. Why not turn this dead plant matter into something useful?. And turn a problem into an opportunity….biochar for soil improvement!.


the twigs and leaf litter have been packed down into the drum and the pipe is removed to leave a central clear column/flue for hot gases.

Pre-Columbian Amazonians are believed to have used biochar to enhance soil productivity. They produced it by smouldering agricultural waste in pits covered in soil. This process is known as pyrolisis, which involves heating the biomass in a low/no oxygen environment. The absence of oxygen prevents combustion.

Biochar is stable, fixed and “recalcitrant’ carbon and its extremely porous nature can improve the water holding ability of soil. The presence of potash can also reduce soil acidity . With its porous structure and high surface area, biochar reduces leaching of critical nutrients into ground water, so nutrients are retained for the plants resulting in a higher crop uptake of nutrients.

In theory, the biochar can help form a habitat for micro organisms, bacteria, fungi and plant roots. This is soil organic matter (SOM) (as distinct from the non living recalcitrant biochar) and so the total carbon in the biochar treated soil further increases. The aim is to achieve a healthy soil ecosystem which can improve plant growth and plant response to disease.


Ready to light.



Resulting biochar tipped out of the drum.


There is still much to learn about complicated soil ecosystems and how biochar may be beneficially used.? To learn more and review much of what was explained on Saturday you may wish to view this 2012 CSIRO “The national biochar initiative” video 8 min

This is just one of numerous biochar videos on the net.

Our thanks to Helmut for sharing what he has learnt from experimenting with making biochar. Even if we don’t try our own biochar making experiment, next time we hear or read the word biochar we all will reflect on just exactly what it is meant with a lot more understanding..

Soil Science is a fascinating and important study. To gain an appreciation how complicated and amazing soil actually (humus) formation is check out the time lapse video at     7 min