Last night, as I was poring through Richard Gianfrancesco’s excellent 2011 book How to Grow Food, I came across a reference to “bokashi composting.” A quick glance online reveals that there are a considerable number of people practicing this method of breaking down food wastes, but I must say, it’s not a practice I’m familiar with. Our municipal goverment is currently making moves to add a composting element to our citywide recycling endeavours, and I have long wondered exactly how they are going to deal with food wastes that don’t fall under the traditional composting categories of “greens” and “browns.” A short turn on Google has led me to the website of the City of Ottawa, which practices a residential organic waste recycling initiative. Ottawa residents can put pretty much any kitchen waste in their green bins – even dairy and meat – and once collected, it is heated to 55°C to kill harmful bacteria and then it is thoroughly filtered (to get rid of any potential smell). The end product is aged for 21 days before it is sold for agricultural use. The City of Calgary will likely follow a similar procedure once its kitchen waste recycling program goes into full swing, but what if you want to deal with ALL of your kitchen wastes on a really small scale, at home, for the benefit of your garden? It turns out bokashi can actually break down wastes such as meat and dairy, unlike traditional composting or vermicomposting.
To clarify, bokashi isn’t actually the same as composting; it is actually anaerobic fermentation, which is basically (to my non-chemist brain) the decomposition of organic matter in a closed, airless system – or as close to airless as possible, given the limitations of the bokashi bin. Composting, on the other hand, happens in an aerobic environment – you need the oxygen in the air to break down that green (nitrogen) and brown (carbon) matter you put in. Bokashi doesn’t yield finished humus, either, as composting will – you should use bokashi in conjunction with traditional composting or vermicomposting and let the fermented product age before incorporating it in your garden projects.
You can purchase bokashi bins in stores that cater to eco-friendly living, and they’re widely available online, of course. The Compost Guy has a description of how to make your own bin using a couple of plastic buckets. It all seems very accessible, even for those of us who lack handyman genes and live in small spaces. And, to make it even more attractive, the bokashi process supposedly doesn’t produce the foul stench of decomposing biowaste that I suspected it might…if you do it correctly. Same as compost, really.
The only real drawback that I can see here is that you need a little supplement to get the whole fermentation thing going…it’s a special mix of wheat bran and beneficial microbes that you need to either purchase or create yourself. You need the microbes on a continual basis, so you must always spend time and money to obtain the mix (it’s not like sourdough starter, unfortunately, and you can’t save over a little bit each time you “harvest” your bokashi buckets).
So, what do you think of bokashi? Is it worth a shot? Are there any of you out there using it, and if so, do you feel it is a successful way to deal with your kitchen wastes?