If you recall, I designed our vermicomposting bin to be a ‘horizontal’ system; we stuck chicken wire in the middle of the bin to divide it into two halves. I thought what we would do was feed on one side, and once that side was ‘finished’, we would start feeding on the other side to entice the worms over.
However, when I really thought about it (when the half of the bin in use started getting full), it didn’t make sense to me. If you kept feeding that half, adding new kitchen waste and bedding, then how would the worms ever have the time to ‘finish’ the compost for you? DNC, dude.
So finally, when our bin got so full that we had trouble closing the lid, I started doing some research. Exactly how is the end of the process supposed to work?
It turns out that what you’re supposed to do is start feeding on the other side of the bin once the first half gets full. The worms very gradually migrate to the new half of the bin, over the course of one to two months. By the time most of them have migrated, your compost should be relatively finished. However, reading between the lines, I gather it’s really not guaranteed.
This is pretty disappointing, because it means that in order to harvest the vermicastings, once most of the worms have migrated, you’ll have to sift through any left over lumps of not fully converted waste or bedding, plus retarded worms who stayed. I’m going to be optimistic and assume that all the waste will have turned into worm poop by the time we go through it, and the only chunky parts left over will be the bedding.
Still, it’s going to be a pain to sift through (I think I will have to get a pretty large sieve), especially since there might be a few worms left (touching slimy things grosses me out completely). Next time I’m going to design a worm bin where that sifting process is automatic. It’ll be truly flow-through!
I want to build a system where the bottom is a screen, and so the worm compost just gradually falls through the bottom (into some kind of collecting tray), no manual sifting required. Maybe a bit of a shake a few times a year, tops.
The inspiration for this idea (not that it’s innovative or anything) came from Bentley’s site while I was doing research. Naturally I don’t plan to make it anything near as fancy, and the real challenge will be to figure out how to achieve the effect with minimal effort (in particular, no carpentry).
I think this is what happens to people who compost with worms. They just start getting obsessed and trying to figure out better ways of doing, well, everything. Or maybe that’s just geeks in general, and the only people who write vermicomposting websites are geeks. Yeah, that makes more sense.