Students Evaluate Bio Char In Soil

Students Evaluate Bio Char In Soil

Biochar at 10% concentration in marigolds.

Horticulture students from Olds College in Alberta, Canada, are investigating the viability of using bio char as a soil additive for greenhouse-grown crops.


The group includes Emily Stanley, Michael Templeton and Heather Hood. Olds has a very good horticulture program, and I graduated from the greenhouse program there in 1996. Because of my involvement in the program, the group approached me to be a mentor for the study. In this role, I had conference calls with the group every two weeks to discuss the status of the project and offer any insight from a professional grower’s perspective.

Bio char is a product derived from a special burning process of organic matter with limited amounts of oxygen. This holds the carbon in the organic matter. When the process is finished, you have a bio char product that can be used as a soil amendment.

The students conducted trials on tomatoes and marigolds, mixing media and bio char at different percentages, with a peat-moss-based soil similar to what we use at Rainbow Greenhouses. The plants then were observed as they grew, with the objective to determine whether this material would be a good fit for a commercial greenhouse to trial in the future. The results showed some increase in root mass, as well as increased shelf life of the plants after stopping fertilizer applications.

The final summary was that there still needs to be more research done on bio char for greenhouse ornamentals. More cultivars need to be trialed, along with further cost analysis, but I can see it may have its place in the future and it is still something that intrigues me.