Worm Composting

Several weeks ago, David asked about composting. Yesterday Mark and I set up a new bin for Mark’s Lover and harvested my bin. We took a few photos of the process.

Punching Holes in the BinThe bin size we both use is pretty small. It’s my understanding that worms only stay in the upper layers of a bin, so I don’t bother with really big bins. This bin is a 10 gallon one, but it’s only 8″ deep. Next time I’d probably get a slightly deeper one, but this works for now.

Mark punched four holes in the bottom of the bin. That way, if it drips, you know the bin is too wet. Some people don’t use holes on the bottom, but if you’re new to worm composting, I’d probably add holes on the bottom.

Around the top of the bin Mark punched more holes, about nine to fifteen on each side, for air flow.

Soaking the PaperMark brought a ton of shredded paper from work to fill the bins. Then he soaked the water. This method was a mistake! The shredded paper was so fine that it all clumped together. You don’t really want this to happen. So if you use shredded paper, I would spray it damp with a mister. You want the paper materials to be about as damp as a wrung out sponge.

Another option is to tear newspaper into strips (the narrower the better) and then soak it in water. When you drain the water, the newspaper still remains fluffy.

The bin should be mostly full with bedding.

Bin with BeddingThis is the bin after I’ve added all the bedding and the unfinished stuff from my harvesting.

Red WormsTo compost, you need red worms, not regular variety earth worms. These red worms are actually an invasive species, so don’t stick them into the ground! You can buy red worms online, or at fishing shops. I went on Craigslist and wrote an “ISO: Red Worms” post and got them from a lady for $5, which was about 1/10th what they would’ve cost to order them. Now I’ve split my worm population twice, once for Mark and once for Troy.

FeedingI pocket feed. About once a week I dump food into a different corner of the bin. Then I cover it with bedding (to prevent fruit flies). I also freeze the food scraps before feeding, which helps prevent fruit flies and aids in breaking down the food faster (because freezing the scraps breaks down the cell walls).

Another method of feeding is to just dump new food on top.

By the time I reach the original corner, if there’s still food there, I don’t feed for a week. The benefit of pocket feeding is that the food scraps are in various states of decay, so the worms can eat what they like.

I feed veggie and fruit scraps, and sometimes coffee grounds. No dairy, no grains, no meats. Go easy on the garlic and onion because worms don’t like it much, and go easy on orange and citrus peels because it can irritate the worms. (Worms breathe through their skin. Have you ever accidentally squirted yourself in the eye while peeling an orange?)

I’m not able to use up all of my food scraps yet, but between saving scraps for vegetable broth and the worms, I throw away very little compostable food in a week.

Every other week or so, I add more bedding to the bin to keep the ratio of browns (paper products) and greens (food products) right.

Ready to HarvestAfter several months, the bin will be ready to harvest. (I should’ve had more bedding in this bin, I think.) I quit feeding for a couple of weeks. In this bin I pulled a lot of the larger pieces of unfinished stuff to one side about two weeks ago. I figured it would make harvesting easier. (I was right.)

Light HarvestingRed worms are sensitive to light. I made several piles of compost on a tarp and waited about five minutes while the worms moved away from the light, to the middle of the pile.

Scraping off CompostWhen the worms were done diving, Mark’s Lover and I scraped off a layer of compost from the top, reformed the conical piles, and waited for the worms to dive again.

We tossed unfinished compost onto my bin lid, where it was later added back to my bin to be finished.

When the piles got small enough, we combined them until we were stuck with two piles of mostly worms and very little compost. We then dumped one pile of worms/compost into each bin.

Finished CompostThis is the finished compost. I need to let it dry out a little bit, and I need to stir it in about a week to find missed worms and newly-hatched worms. I’ll also run it through some wire mesh to make the clumps the same size. Then it’s ready to be used!