Bokashi composting
8:34 am in Getting Started, Projects in Process by Trygve Henriksen
A log of my experiences with bokashi-type composting.
I will be using the ‘compost tea’ drained from the bin as fertiliser on potted plants and as nutrients in my WF.
Note, it’s not critical to buy an ‘official’ bin for this type of composting as it looks doable to make your own. You will need the bokashi bacteria mix, though.
To make your own bin, get two buckets where one must have a lid that can easily be sealed tight.
On the bottom bucket, you’ll need to affix some sort of spigot to drain the liquid. An old water container, possibly those large cardboard wine boxes or similar may have one that can be glued in place? Affix it as far down as possible. (If you have flexible tubing, you can glue in a piece of that, and just clamp it shut)
The other bucket – the one that will have the compost – drill a lot of small holes 1/16″ or so should do nicely. Try to space them 1 – 1.5″ apart.
Place the compost bucket on top of the one with the spigot and seal tightly. It’s nice if the compost bucket slides into the other. You don’t need more than about 1″ of height in the ‘sump’. Place lid on top…
That’s all there is, really, a large bucket with a sealed lid, and in the bottom some drainage holes that leads to a sump that can be drained with the spigot.
If you don’t want the ‘compost tea’, all you really need is a normal bucket with sealed lid. (place a grate or something in the bottom to create a chamber for the liquids to collect in, then dump them later when you empty the bucket. Or you can use two buckets stacked into each other, just leaving the spigot from the design.)
Usage.
This part is written as I experiment, and each new entry will be datemarked as I write. Some parts may still be inaccurate or even wrong when I finally post this… Assume that old date means it has been tested longer and that I probably removed what I later learned to be incorrect.
== August 4, 2010 ==
(Received bin and bokashi matter)
Started it off by covering the bottom with a generous amount of bokashi matter, at least 1/8″ or so thick. Then start throwing in waste food with a sprinkling of b.m on top.
It may be a good idea to collect the waste in a jar or something and only throw it into the bokashi bin once every day. Cutting the waste into small pieces is highly recommended.(1/2″ cubes or smaller)
While dumping liquids into the bin isn’t exactly recommended, dumping all-dry materials won’t do much good either. So stay away from thin soups and massive amounts of all-bran or old flour.
The most liquid I’ve felt safe in adding has been small slumps of jam, very old tomato puree and yoghurt.
== August 18, 2010 ==
The ‘Compost tea’ may contain debris and large particulate and should probably be filtered. For that reason I’ve bought a pack of 100 coffee filters, and I intend to cut them into 4 parts(each side being cut in half) for a total of 400 filters. I bought filters of unbleached paper.
Used filters can probably be recycled just by trowing them in the Bokashi bin, as it is biodegradable and doesn’t contain any bleaches.
Also, running the WF for two weeks without changing the water, just topping up and adding compost tea doesn’t seem to be a good idea. My system started smelling and the reservoir needed a thorough cleaning. (Large particulate may have been a contributing factor?)
== August 30, 2010 ==
The Bokashi bin is nearing full. At this rate it looks like it can hold about 1.5months worth of organic waste from my home, but I know that it’s slightly misleading in two parts.
1. When I started using it, I ‘started it off’ by adding a lot of very old food (tomato puree with a best before day a year or more ago, some freezer-burned meat, and a lot of spoiled vegetables), and that situation is now much less severe.
2. As my WF gets up to speed and veggies start producing, I will no longer have to buy as much vegetables in the stores. Most packaged vegetables comes in too large packs for my consumption, so some is inevitably spoiled.
Anyay… Another thing I’ve learned recently is that the bin is NOT completely odor safe. Raw fish parts(particularly guts) definitely leave a recognisable odor even if you use ‘liberal amounts’ o the Bokashi material. Of course, this is a problem I can get around by cleaning the fish where I catch it, instead of bringing it all home with me.
I should probably start looking for some buckets to make a ‘spare’ bin soon, before the current one is full, as the full one needs to sit for two weeks before dumping the contents into a normal compost.
Also, I may be able to get a $150 discount on the renovation fee if I can get the local authorities to accept this system in the same way they accept ordinary composting. (We have recycling, with 3 wheelie bins; organic waste, paper, ‘the rest’. Plastic goes into large bags. Glass and metal is delivered to centrally placed containers. Those with a ‘composting contract’ only have two wheelie bins. )
== September 1. ==
For different reasons I haven’t been draining the ‘compost tea’ for a week or so, so I expected there to be ‘a little more than usual’ today.
Seems raw fish contains a lot of liquids… including oils and whatnot… It was also NOT odor free. Thankfully I have whole bags of incense from my trip to Thailand this year…
Also, picked up a pair of 5L buckets in the hope of building a spare bucket.
== October 1. ==
Bokashi bucket is full and in the two week waiting period with lid closed.
I’ve also made a new one out of the two 5L buckets I bought earlier.
(I drilled a hole and epoxied in a piece of tubing to act as spigot, and just use a plastic clip to squeeze it closed.)
The stink problem after the fish remains may have been partially caused by using too little of the bokashi mix, but I don’t feel like experimenting on it, and will in the future remember to always gut and clean the fish when I catch it, not when I get it home.
Needed a better way of storing the Bokashi mix(it was in a zip-lock bag), and settled upon an empty XL1 sports drinks container. (The normal 650gram container won’t take the full 1Kg bag, though. On the other hand, it’s a handy size for sprinkling the mix, and the lid IS pretty darn tight)
== October 23. ==
I left the bucket to rest over 3 weeks before taking it out on the verandah and dumping the contents into a plastic container I had prepared with alayer of soil and lots of dead plants. I mixed itup a bit and covered it in more soil. The compost in the bin was pretty much a solid block of decomposing organic mass, with very little recognisable.
I think I may have overdone the first layer of B.M and used too little lateron in the process. It’s cold outside(hovering near zero in the day, even snowing sometimes, but on the underside of the transparent lid on the container, there are now large drops of condensate. I take that as a sign that there’s some activity in there.
My home-built bucket may or may not work. I have yet to be able to drain a single drop of compost tea from it. It’s possible that the contents are too dry(mostly teabags… ) or that the lid isn’t tight enough so that it allows evaporation.
Now to clean my Bokashi bin and prepare it for use again.
