Commercially available Bokashi spray isn’t extremely expensive (at about $10 for a bottle here in OZ). You don’t need much of it either, so a bottle will last a long time. So why make your own? My answer is always ‘because we can’. It’ll save you a few dollars over the long run and give you a little touch of independence too. Also, it means that you don’t have to buy a plastic bottle every time you need some.
EM1 is a commercially made, carefully researched solution the includes a range of microbes that will do the fermenting in the Bokashi bin. In the solution, they’re just waiting for something to eat so that they will have the energy to reproduce.
That means that once we’ve got our hands on a sample of the microbes, we can breed them up into large numbers just by giving them the right food and the right conditions for microbial love to blossom.
I make ours at a rate of two 1 litre bottles at a time. The contents of the list below will make you litres of the finished liquid. It is very simple and scalable.
All you do is mix the molasses and water. Mixing Molasses can be a bit messy as it never seems to all dissolve at once. I’ve found that mixing it a splashe at a time in a small jug is the best way to mix it. Keep adding the mixed molasses and water to your final 1 litre container.
Once the molasses and water are mixed and in your bottle, add the optional seaweed fertilizer and swirl it around to mix it. The seaweed fertilizer is an optional nutrient boost for the microbes. Then you add the EM1 solution and gently shake the bottle to make sure that it’s well distributed throughout the bottle.
Before you tighten the lid, squeeze the bottle enough to put a visible dent in one side. This will help you know when the culture is ready. Then tighten up the lid.
Leave the container in a warm place and away from direct sunlight for a few days. The time will depend on the temperature – in Winter it can take two weeks if you’re doing it outside. I find it best to leave it on top of our fridge where it is always a little warm.
When you inspect it (it’s impossible not to sneak a look) you may notice small bubbles forming on the surface. This is carbon dioxide that comes from the activities of the microbes in the mix as they eat the molasses and optional Seasol and breed like crazy. This activity may also cause the liquid to warm up a tiny bit too. Probably the best telltale sign is that the colour of the liquid will be getting lighter as the microbes digest the molasses. You may also notice a little sedimentation at the bottom of your container. I assume this is composed of dead microbes or solidified waste from the critters in the mix.
As the microbes go about their lives, they produce carbon dioxide gas. This will fill the bottle and push out the dent in the side. When you see that the dent has gone, you’ll know that there has been lots of microbial activity. Left unattended, the carbon dioxide will build up enough to really push out on the sides of the bottle and there will be a noticeable hiss when you open the bottle.
When you open the bottle, there may be a hiss as the extra gas escapes. That’s a good thing! Smell the liquid too. There should be an odour that smells like a blend between molasses and a slight vinegary smell.
You can keep the original bottle that you bought in the fridge and keep taking out 20 ml at a time and making a new batch. Otherwise you can keep making batch after batch by simply taking some of the batch that you’ve made and repeating the process. Every few batches though, I’ll use solution from the original, purchased bottle to keep the new stuff strong.
When you reckon it’s ready, pour some into your spray bottle and use it just as you would the original solution.
Bokashi is a fascinating process. The more I learn, the deeper I get into it. There’s more information about it and how you can use it around your home on our Bokashi page.