Garden & Greenhouse


Understanding Biochar

Posted March 29th, 2019 by Garden & Greenhouse in , ,

Biochar is simply the carbonization of biomass, essentially charcoal.  Heating biomass from vegetable and animal waste with little or no oxygen at a suitable temperature produces Biochar.

When used as a soil amendment, Biochar improves soil function by holding carbon, making soils more fertile, and providing a permanent habitat for soil microorganisms. Biochar holds carbon and other nutrients because of its unique structure, full of pores and surface area. It is an excellent habitat for beneficial bacteria and beneficial fungi. This nutrient holding property of Biochar is particularly useful in areas that flood often or farm lands that have been over farmed.

Further, because of this unique holding property, Biochar has the ability to attracting and hold moisture, nutrients, and important chemicals, specifically nitrogen and phosphorous. As every farmer knows, nitrogen is one of the most important chemicals but it tends to run-off regular soils potentially upsetting the ecosystem balance in nearby streams and ponds. Biochar holds gasses as well; recent research has proven that Biochar enriched soils reduce carbon dioxide (CO2) and nitrous oxide (NO2) emissions by 50-80%. Both nitrous oxide and carbon dioxide are problem greenhouse gasses.

Benefits of Biochar

The use of Biochar will increase crop yields and improve soil fertility for the long run – not just for one season. Biochar remains in the soil and a single application can provide benefits for years. Many years of research has shown that Biochar stimulates a wide variety of beneficial soil microorganisms. The pores in the Biochar provide a habitat for the microorganisms by protecting them from drying and providing them with a long-term carbon source. A carbon source is essential for bacteria and fungi to thrive and multiply.

Advantages & Disadvantages of Charged Biochar

Biochar is often charged, sometimes called activated, by using compost or compost tea. There are also a number of disadvantages to charging Biochar with compost as well.

  • The compost may not be of good quality or be well balanced – bad compost may do more harm than good!
  • Some composts do not contain all the necessary microorganisms.
  • Manure used to charge Biochar may contain antibiotics, insecticides, fungicides, or worse – manuremay contain pathogenic (disease causing) microorganisms.
  • It takes 2-4 weeks before the microorganisms in the compost colonize the Biochar. This results in unnecessary delays in applying your Biochar.
  • Biochar quality will vary with each application depending on the type and quality of compost.
  • The structure of Biochar is designed to allow microorganisms to attach and form colonies. From the beginning use of Biochar it is best to add microorganisms that are known to be beneficial.

Bill Baugh is a product manager for Custom Biologicals, Inc. a manufacturer and distributor of innovative microbial products. You can visit their website at and he can be contacted at 561.797.3008 or

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