What is Bokashi?
It’s anaerobic (air-free) fermenting of food waste
Bokashi means “fermented waste”. Bokashi composting is:
Originally from farming traditions of East Asia
Anaerobic
Homolactic fermentation
Driven by lactobacillus and other effective microbes
The bokashi process produces relatively dry pickled compost to feed sub-soil microbes directly.
How does bokashi work?
When food scraps are placed in an airtight container along with microbes that thrive without oxygen, it ferments. Simple!
To carry microbes to the food waste, we use organic wheat bran that we inoculate with Effective Microbes, a mix of beneficials originally developed by Dr Teruo Higa.
The Bokashi Process
Vessel Selection: Choose a container that’s airtight with the ability to drain liquid.
Prep: Close drain valve and insert the grate into the bottom of your bucket. Sprinkle MO-kashi bran on the grate.
Fill: Add food waste, sprinkling MO-kashi bran between each layer. Pack down to remove air. Repeat until full. Seal lid tightly.
Fermentation: Store the full, sealed bucket for 14+ days, draining the leachate out of the bin every 2 days. Do not open bin during this period as oxygen will disrupt the anaerobic fermentation process.
Use: After 2-3 weeks your bokashi is ready for use! We suggest burying in the garden, feeding to composting worms, adding to an outdoor compost pile, or feeding to poultry.
Repeat: Start the bokashi composting process over!
Why were we drawn to bokashi? During thermophilic composting over half of the mass of the food waste and supplemented carbon was consumed by microbes and released into the air as various forms of carbon, including methane. Bokashi loses only 5% of the mass and retains more of the nutrients in the food waste. Hot composting produces wonderful undifferentiated organic material and is easy to handle for top-dressing on beds or using in seed-starting mixes so we will continue to make hot compost, but bokashi is the superior method to directly feed subsoil organisms in the plant root zone and with our focus on soil health this is a winning argument. Plus it doesn’t generate greenhouse gases, is a suitable food source for worms, and doesn’t need continuous application of water and an initial load of wood.
Finished bokashi is perfect for incorporation into the root zone — it’s highly available for soil microbes — so when we build new permanent beds we like to trench the future bed and lay a thick layer of bokashi in a 6” zone from roughly 10” to 4” below the top of the bed. After allowing several weeks for earthworms and soil organisms to digest the bokashi we plant cover crops to cycle the nutrients before transplanting flowers and herbs into the bed. We also make hot thermophilic compost from the bokashi — it heats up really quickly and evenly and produces excellent compost while avoiding some of the most common problems of raw food hot piles.
Composting worms also eat bokashi, and we’re really happy with bokashi as a feedstock. We had previously fed unfinished compost, pulling the worm food after the pile had come up to temperature of at least 130 degrees for 4 days to meet US Composting Council recommendations, and while the worms did well on this the immature compost was roughly 50% wood chips (the main carbon source for hot piles) and adding more than a very thin layer would lead to the bin heating up as the compost continued to cook. Bokashi avoids this, and is also more nutrient dense as it’s purely fermented food waste. As we expand our worm bin we will continue to feed bokashi to the worms in greater quantities.