JoAnne Skelly: Bokashi composting

Haley, an AmeriCorps intern at The Greenhouse Project, introduced me to Bokashi composting recently. It is an anaerobic (absence of free oxygen) form of composting, using fermentation to decompose kitchen waste.

This composting system began in Japan and Southeast Asia according to author and permaculturist Adam Footer in “Bokashi Composting: Scraps to Soil in Weeks.” Its effectiveness lies in the addition of a specific group of microorganisms to food waste stored in a special Bokashi bin. It is a good alternative for someone with limited space that would rule out having a large outdoor compost pile, but who still has a place to bury the fermented product.

“If you have enough room for a few five-gallon buckets, then you can compost all of your kitchen waste, keeping it out of the landfill and ending up with a finished product that will add a lot of organic matter to your garden,” (Footer, 2013).

This fermentation process is reportedly odor-free and perfect for the kitchen. It doesn’t generate heat and doesn’t require the mixing of green and brown vegetable matter as does regular composting. It doesn’t attract insects or animals because it is a closed system. Supposedly, it is easier than traditional composting. With the Bokashi method, you can even compost meat, cheese, fish and other protein-based items, something you can’t do in regular composting.

After undergoing an acidic anaerobic fermentation for approximately a week to two weeks, Bokashi pre-compost is produced. Since the material is fermented, it doesn’t look like regular compost. It looks quite similar to its original form. However, at this stage it can be rapidly digested by the soil organisms. It gets buried directly into the garden where it will take a month or two to be finished in the soil. The finishing time is dependent on the soil temperature and moisture. You bury it and let it sit there. Soil organisms break it down further and it builds and feeds the soil. Another way to use the precompost is in a worm-composting bin.

I want to try this method. I would rather buy a Bokashi bin than build my own, since it comes with a spigot at the bottom to drain off the fermented liquid, called Bokashi tea. The tea can be diluted and used as a fertilizer. The beneficial microorganisms are introduced on a Bokashi bran mix. Following the clear guidelines in the book, I should have good soil for spring planting!

JoAnne Skelly is Associate Professor & Extension Educator, Emerita at University of Nevada Cooperative Extension. She can be reached at skellyj@unce.unr.edu.