Worms! Worms! Worms!

Last weekend I finished a project that’s been on my list for close to a year: I started a vermicomposting system. In case you aren’t familiar with the concept, vermicomposting is a composting technique that uses specific species of worms to turn food waste into a fantastic fertilizer (read: worm poop).

I’ve vermicomposted on and off for a few years in college and afterwards, using a plastic bin with drainage holes drilled in the bottom. This setup worked fine, but despite the holes the compost tended to stay very wet, which I suspect encouraged flies and unsavory smells to take hold more than they should. Vermicompost should not smell bad at all.

This time around I decided to build a wood box with a better engineered drainage solution. I’ve heard mixed reviews of using wood containers, but my thinking is that the exposed wood would help regulate moisture by absorbing water when it’s overly wet, and release it if the compost dries up too much.

Finished worm box (sans lid)

The drainage system is a ~1-inch deep “tray” in the bottom of the bin, covered with a fine screen (actually some sheer polyester fabric). All the composting action happens above the screen, but if it becomes oversaturated then water should drain through the screen into the bottom.

I also added a sealable spout for easy draining of the excess water, by repurposing the top of a plastic soda bottle and using tons of silicone.

Inside view of tray and drain spout, with screen removed

I bought 1/4 pound of red wigglers from a very nice local woman selling worms from her own composting system, but realized it would take too long for them to repopulate to fill the bin. So I re-upped with another half pound or so from a live bait shop. Hopefully the hippie organic worms will get along with the more rough-around-the-edges bait worms.

I’ve been slowly ramping up feeding them scraps this week, and will be figuring out what a good steady-state amount to feed them while they grow into the container. But I think they’re happy so far.

For anyone considering setting up a vermicomposting system like this, I highly recommend reading Red Worm Composting. It’s a great combination of anecdotes and more scientific information about this style of composting.