If you’d like to pick an argument in the mostly staid world of gardening, I can’t think of a better subject than compost tea. I’ve, somewhat cowardly, tried to stay out of the fray and leave the debate to Linda Chalker-Scott and Jeff Lowenfels. If you forced me to pick a side I’d lean towards Chalker-Scott’s skepticism.
Thankfully, I can now point towards the eXtension.org webinar on making and using compost teas that I’ve embedded above. I’ll oversimplify things a bit with a few of my own bullet points inspired by what Dr. Lynne Carpenter-Boggs, Associate Professor of Sustainable and Organic Agriculture at Washington State University and Catherine Crosby, a Ph.D. candidate in Soil Science at Washington State University had to say in the webinar.
- Due to a lack of research no peer reviewed recommendations can be made on the use of compost tea.
- Nobody agrees on what compost tea is or how to brew it. What kind of compost do you use? Do you have to aerate it? How and for how long do you aerate it?
- Compost teas have been shown to both solve and cause disease problems.
- Compost tea shows promise as a fertilizer.
- If you add sugar to your tea you need to be very careful about food safety issues.
- You must dilute compost tea before using.
- The compost going into tea must be mature and of high quality.
- You might be better off just applying normal compost to the soil.
My personal conclusions are that if I were a farmer (which I am definitely not), compost tea might be worth looking into as a fertilizer or, in certain specific circumstances, for disease control. As a home gardener, however, I’m going to wait until there is more research before I spend money on a subject that is still so unresolved.
Let us know what you think–leave a comment!