Trending among gardeners is the term biochar.   What is it and why might it be important to you?

Biochar has become a hot topic in the gardening, farming, and climate change fields in the last ten to fifteen years.  (The articles in the bibliography at the end of Gardening with Biochar date mainly from 2006 to 2017.) A gardening friend mentioned Biochar to me one day and I decided to research it.  I have now read two books on the subject, and this is what these two books present.

 Book I: Gardening with Biochar authored by Jeff Cox (2019)

Mr. Cox is the author of twenty-one books on subjects ranging from gardening and cooking to wine.  He was a managing editor of Organic Gardening magazine and is a contributing editor to the publication Horticulture. His home is in Sonoma County, California.

Book II:  The Biochar Solution: Carbon Farming and Climate Change authored by Albert Bates (2010)

Mr. Bates has a varied background and career.  He has a college degree in political science from Syracuse University and a law degree from the NY Law School. He practiced environmental rights law.  Mr. Bates also has a certificate in forest management as well as in several other files. He has authored several books and is founder of intentional community and ecovillage movements.  He instructs others in village design and permaculture.  His book is recommended by Mother Earth News.

 Things I learned from Gardening with Biochar

This book describes clearly how biochar works and its environmental benefits.  Biochar is pyrolyzed charcoal. Pyrolyzed means that the feedstock (wood and other organic material) is roasted, not burned, usually at a temperature of over 660 degrees with limited oxygen.  Research shows this process has been used in ancient cultures such as in the Amazon Basin of South American and in Africa.

Biochar benefits include:  

(1) the charcoal produced by this roasting method retains the chambers and pockets in the original material (channels of xylem and phloem) which provide homes for a variety of soil microbes;

(2) it has a friable crumbly texture;

(3) it holds oils, sugars and proteins produced by microbes;

(4) it increases the capacity of the soil to hold water and reduces leaching of nutrients during rain and irrigation;

(5) It sequesters carbon for a long time, reducing emission of CO2 into the atmosphere. 

Gardeners must realize that biochar is not a nutrient or food source for microorganisms, and it may increase soil pH which may not be desirable for certain acid-loving plants.

Mr. Bates also describes how a home gardener can make biochar in a couple of different ways (in a V-shaped pit or in a metal can), and how important the type of feedstock is in determining the biochar grade and texture, as well as how different grades should be used.

This is an interesting book and certainly makes you want to know more about the subject.  However, after reading this book, I still have questions about biochar’s use. 

1. For instance, it isn’t a simple process to make biochar properly, and to follow the directions to inoculate the biochar with compost, manure and worm castings.  I wonder if the results are worth the effort for the backyard gardener? 

2. If you purchase biochar, is the cost reasonable when compared to the results you will get?

3. Can using biochar in the backyard garden effect not only the health of the garden, but in some small way help preserve the earth’s environment?

 Mr. Bates’ book, The Biochar Solution, is quite different from Gardening with Biochar. It is a much more complex book that emphasizes the big picture.   It has a much broader scope and covers the issue of climate change more broadly and also traces the history of agricultural across the world, the history of population growth, the use of chemical fertilizers, and climate change. It describes several projects focused on how to reduce climate change: reforestation, reducing the salinity of soil caused by chemical fertilizers, building the fertility of soil, sequestering greenhouse gases, retarding the desertification of land, and organizing carbon negative communities.  It also tracks various climate conferences in 2009 on these subjects, including the Royal Society Conference, the UN Convention to combat desertification, and the North American Biochar Conference in Colorado in the same year.

There is also specific information on the biochar process, use, construction of stoves, and the creation and use of compost teas.

 I recommend to you both books.  Each provides valuable information for home and community gardeners to understand the issues facing agriculture, the climate, and the life we enjoy on this “blue dot” in the universe.

 Holly Sparrow, Headwaters Master Gardener