Garden & Greenhouse


Biochar an Ancient and New Technology


Biochar is one of the hottest new amendments to hit the gardening community since Mycorrhizae. As with most new products, the information swirling around the internet and in stores can be confusing. Biochar is a tool that, if used correctly, can create long lasting benefits in your garden’s soil.  However, as with any tool, its effectiveness depends on how you use it.  Before diving into the char of the matter, here is a brief description of the history of Biochar.

Much of the information that we have today on Biochar used in antiquity comes from the indigenous populations of the ancient Amazonian basin. In this region of South America we find a rich history of agriculture and organic land management before the term ‘organic’ even existed. The mystery and subsequent rediscovery of Biochar came when ethnologists and archeologists descended on the Amazonia basin region just outside Brazil. The anthropologists discovered very dark patches of earth in the zones they were excavating. The locals called this area “Terra Preta” or Dark Earth. These pockets of anthropogenic soil contained char, bones, manure and composted humus. These sediment layers were created over a period of several hundred to several thousand years of active site management by the peoples who inhabited the location.

To make Biochar today, we use drastically different methods to produce a large enough quantity to meet the needs of the agriculture industry. Today’s technology includes large equipment called pyrolysis machines. To produce Biochar in one of these machines, two key factors are observed. The first is a very low oxygen environment while heating the material. The second is the temperature at which the Biochar is made. An optional and arguable third criterion would be the feed stock used in the process. What many Biochar researchers can agree on is that the hardwood feed stocks tend to produce a more uniform and consistent Biochar product when finished.

The benefits of using Biochar are being updated on a daily basis as research comes in. The basic areas that Biochar has been shown to improve are soil fertility, microorganism population density, and nutrient management and run off abatement. The peripheral benefits are more comprehensive and possibly more important from a global perspective. The use of Biochar in soils has shown an ability to sequester carbon and offset Co2 emissions. By using the agriculture feed stock approach, one could close the loop on Co2 emissions created by the production of agricultural goods.

Lastly, when using Biochar, one must consider the implications of using it incorrectly and how best to use the product in order to maximize its benefits. Knowing that Biochar can sequester carbon and reduce fertilizer run off, one should be aware that, if using pure Biochar, the potential for over fertilizing and over watering is possible. Because the Biochar is so absorptive, it is possible for it to absorb large amounts of nutrients and water and then store them in the soil for a long period of time. For this reason, it is imperative to use Biochar in

a blended amendment format, or to use it sparingly in your soil and diagnose each soil situation differently. As mentioned at the beginning of this article, Biochar is a tool and must be respected as such. Use this tool correctly in your gardening repertoire and you will never have to buy mass quantities of soil again plus you will save money on input costs for your garden.

Mark Ervin is the president of GreenGro. He can be contacted at 866.884.6803 and

Want more information? Read these articles:

Four Great Natural Fertilizers

Requirements for Successful Soil-Based Vegetable Gardening

Soil Amendments in a Changing World

Using Amendments for Soil Management Practices

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