Chances are you’ve noticed by now that I’m very passionate about reducing food waste. I mean, come on, not only does organic matter sent to landfills emit copious amounts of methane (one of the greenhouse gasses), but it robs the agricultural sector of the cheapest (if not to say “free”), most effective and safe source of fertilizer ever! Furthermore, when a resident dumps food waste into trash, he or she is actually paying for the local waste management company to haul the waste to the collection site… Anyways, this post is not about why food waste is bad (although of course it is!), but about a fairly new approach to tackling it in a small household setting, when traditional composting is not an option.
So what is Bokashi?
In horticulture, Bokashi refers to fermenting organic matter with anaerobic bacteria (most often Lactobacilli, often called “effective microorganisms”, or EM), followed by final decomposition in the soil. In an ideal system (warm enough, not too moist, not too dry) the whole process takes only four weeks – isn’t it amazing?
What are the pros and cons of Bokashi, compared to conventional composting or vermiculture?
- Pro: It barely takes any space, so great for apartment dwellers like yours truly.
- Pro: You can process any organic matter, including bones and other animal products.
- Pro: It is fast! In optimal temperatures, the whole process takes four weeks.
- Pro: It’s cheap – the only thing you really need to purchase is the Bokashi EM-inoculated bran.
- Con: You do need a spot in the ground to bury your fermented mix – possibly in a friend’s back/front yard? I am thinking of an experiment with a soil-filled bucket on a balcony for this purpose – will let you know how it goes!
There are a lot of kits and setups for Bokashi composting on the market, but in my experience, they are not necessary – all you need is the inoculated bran (this one you do need to purchase) and a container of your choice (anything with a tight lid). Now let me show you how I do it.
You start, or course, with organic matter. In this example I’ll be using watermelon rinds, because they are more sightly and because I had a ton of them when preparing for this post last summer (yes, it took me a while to finally write it…). The cool thing about Bokashi fermenting, though, is that ANY kind of organic matter works, including bones and hair, as well as things like onion and citrus which you can’t put into a worm bin. I prefer to chop up the fragments, so that they take up less space.
I place the fragments into a container. I’m using a glass jar in this example, because it is see-through, but for routine use I actually prefer jars with wider openings, so that it’s easier to compact the contents.
After filling the container with a few inches of organic matter, I sprinkle Bokashi bran over it. The ideal conditions for fermentation would be achieved if I actually mixed it in, but that is more hassle than I like to take on, and it works anyway.
Depending on the type of organic matter, you might need to add some liquid. Watermelon rinds have more than enough, but dry things like salad greens, flour or old herbs need extra water.
I keep gradually filling the container with organic matter, sprinkling in some bran and compacting the contents as I go (I use my fist, but some people prefer a potato masher). While the container is being filled, I keep it in the fridge. The Bokashi microorganisms are anaerobic, meaning they prefer environments low in or devoid of oxygen, so until I can provide these conditions, I keep them dormant by maintaining low temperature.
Once the container is full, I close the lid tightly and label it with a date when the contents are ready for the next step (two weeks from the date the container is full).
The jar then goes into a warm spot (a kitchen cabinet that I don’t use much because of its location).
Two weeks later, we can move on to the next step. You can also let it ferment longer, two weeks is just the minimal time required for complete fermentation. The time needed may also vary based on the temperature. For example, if the containers are sitting somewhere cold (that is, cooler than 70F/20C), you should let them go for three weeks or longer.
Now comes the burial! May sound overly dramatic, but I can’t come up with a better term for this step :). After the two-week-long anaerobic fermentation, the mix should be put in the ground and covered with at least two inches of soil (I just dig all the way to the bottom of my raised bed, which is about 8 inches at the moment.
What happens now is that the Bokashi microorganisms, along with the flora already present in your garden soil, will finish the decomposition. And after another two weeks the unsightly clumps of fermented organic matter will be gone!
As with the anaerobic fermentation step, the speed of decomposition will vary based on the outside temperature. The example batch here was processed during the summer, but when I bury the mix in the winter, it obviously takes much longer to disintegrate. Still, it will happen, and if you bury it deep enough, you can proceed with your gardening on top of it.
As you are emptying the fermentation containers, go ahead and rinse them with water and pour it into your garden beds – this is a solution rich in beneficial microorganisms, which will go straight down to business in your soil.
So here it is, my Bokashi method. Not that complicated or time consuming, is it? I hope this post encourages you to give it a try!