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Vermicomposting: Black Gold and the Power of One

Summer 1999 Newsletter

Worms are the perfect pet. You can keep them in an apartment without violating your lease. They are quiet, odor free, always know where to "go", no vet bills, no food bill, won't die if you forget to feed them for a few weeks, helpful and fun to watch…okay, if you want affection, look elsewhere (but some people say that about more traditional pets). Worms are chic.

I have yet to hear a worm-owner say anything negative about his pets. And people at parties seem much more interested in worm stories than cat adventures.

If you read my first report as a neophyte vermicomposter ("The Worms Crawl In", Fall '98 Guardian Messenger), you may be wondering if I ever replaced my garbage disposal. I have not. I think composting kitchen garbage with worms is a great project for any size dwelling and any size family.

You simply need to adjust your container size and your worm population to fit your particular needs. This article is really intended to be a "how-to". It is not hard to compost with worms, and you can do it with very little initial investment… so what have you got to lose?

How do you get started? First, weigh your garbage! Put all your kitchen waste each day into a large coffee can or other container with a lid. Weigh the waste every day for a week or more to get a good idea of how much you toss. 2000 worms can eat a pound of waste per day (leave out meat and fat… your dog will like it, and worms get indigestion).

Next, you need a container. Be creative. An old dresser drawer, a wooden barrel, a trunk—wood is more absorbent and a better insulator than plastic, but anything can work. You need one square foot of surface area per pound of kitchen waste per week.

The container should be eight to twelve inches deep. Good drainage and air are essential, so you will need many 1/4 inch holes in the bottom and top. A sheet of dark plastic or burlap can work as a cover inside, but a secure lid is needed outside (many critters think worms are yummy).

Worms need to live in soil temperatures between 40° -90° F, but they prefer warm room temperatures. A basement is great, but anywhere convenient is fine as long as you watch the temperature. Be sure the lid lets in lots of air. Raise the bin on bricks and place a tray underneath to capture excess liquid. Save the collected liquid to fertilize your houseplants.

Now, a comfy — and edible — bed. Line the bottom of the container with garden fabric, which is porous for drainage but won't let worms fall through. To provide varied nutrients for the worms and thus a richer compost, mix together an assortment of shredded newspaper and cardboard (no colors or gloss), shredded fall leaves from a low-traffic area, chopped straw, seaweed, sawdust, peat moss, and some aged compost or manure.

Watch it! Lots of dogs, cats, cattle, and horses are "wormed" regularly. That makes their waste toxic to your worms! Throw in a handful or two of fine sand. Like birds, the grit aids the worm's digestion.

Worm bedding needs to be slightly damp (like a squeezed sponge) organic matter that takes a long time to decompose, and doesn't heat up too much as it rots. "Fluff" the bedding to let in air, discourage odors, and provide wiggle room. Initially, the container should be 3/4 full of bedding.

It's time for the worms. If you are adventurous, you can look for your own just under the surface of a manure or compost pile. If you prefer capital intensive adventures, surf the web for your worms.

There are many worm farms with web sites. Most redworms are sold through the mail. Just type "worm" into a search engine. If you are trying a bait shop, ask for "red wigglers" or "brandlings".

Make sure you get the right sort of worm! You've probably seen redworms before, when you turned over some old wet leaves or straw. They start out life very small and nearly transparent. As adults they grow to only a few inches, and their color ranges from a light red, to a deeper red, to purple.

But, redworms are not the earthworms you see in the garden. Earthworms are more than twice as large and they like to live deep in the soil, feeding on fairly decayed matter. Redworms are surface dwellers that eat their own weight in recently decaying organic matter each day.

Once you have bedded down your worms, you only need to feed them every other day or so (you can add a full layer of waste all at once and go on vacation for two weeks without worry). Make sure your bin stays moist.

Collect coffee grounds and (smashed) egg shell for proper balance. Add poultry feed or ground corn to fatten up the worms and make them reproduce faster. Any vegetables, fruits, peels, etc. are okay.

Worms will eat onions last, don't like citrus, and take long enough to eat dairy, grains and animal proteins that you can get into odor, rodent, or bug problems. Worms are like Zen monks… feed them a pure diet. Be sure to "bury" the new food when you add it by lifting the surface layer and tucking handfuls underneath.

If you have trouble with smell or fruit flies, you probably are suffering from a lack of oxygen. "Fluff" the bed. Put a piece of bread on the surface, wait a few days, then remove it with any maggots attached. (Okay, it is gross, but it solves the problem.)

So, what do you get from this labor of love? First of all, you get the satisfaction of not wasting your waste…and not trudging through snow drifts to add it to the garden compost.

Second, you learn a lot about your own eating habits. You will become much more aware of how much you waste, and of how much fat and animal product is in your diet.

Best of all, you get Black Gold! Liquid gold drips through the bin, and, every three months (maybe a little less), the worms will have eaten all their bedding and all their food, reproduced like worms, and left behind their black, moist, nutrient-rich "castings" (a.k.a., worm manure).

"Black Gold" is an appropriate name for this precious stuff. (It is even sold under that name in some gardening shops!) Add a teaspoon of compost to your houseplants every week or two.

Mix compost (one part) with potting soil (five parts) for the best seedlings ever. I have heard that only pumpkins can grow in pure worm castings, but maybe that's the secret of those gigantic pumpkins. Use it sparingly because it is extremely potent.

There are several ways to harvest your compost and re-start your bin. The easiest way is to be really fancy at the start and create a two-or-three layer bin so that your worms can crawl up to the next layer as they finish eating the lowest layer.

In this method, you feed into the bottom layer until it seems almost completely eaten, then put the next layer (with little crawl-through holes drilled in the bottom) on top and start putting the food in the top layer. Your buddies will eventually all crawl through. Then it's easy to remove the bottom bin, harvest the castings, and set it aside for a repeat.

System number two takes advantage of redworms' hatred of the light. The worms will wiggle deeper into the bin to avoid it. When the castings outweigh the remaining bedding, place the opened bin under a very bright light for two minutes.

The coast will then be clear to scrape away castings from the top layer. Keep going, using the light to clear the way. When the harvest is complete, fill up the bin with fresh bedding and start over.

The final suggestion is to hire eight first-graders, dump the bin on plastic sheeting, and have the kids pick out worms. Don't miss all the egg cases (lemon-shaped, tiny cocoons which each hold between two and twenty baby worms). Mix a little of the finished compost in with your new bedding layer, and bag the rest of the compost in plastic bags.

Are you a capitalist at heart? Bait shops buy red wigglers from private growers (so do people who want to start composting). Your compost also has a market value. Pre-mixed potting soil would also sell.

Whatever tack you take, worms are fun! Check out some websites before you get started. Enter "vermi-composting" at web search engines, or begin by looking at these sites:

www.cityfarmer.org
The Canadian Office of Urban Agriculture's site for listings of books and newsletters, as well as links, an excellent glossary, activities for children, and a worm sources page which lists distributors of bins and worms.

www.wormdigest.org — yup! There is even a magazine called "Worm Digest".

Have fun! In Canada there is a group that sells T-shirts promoting vermi-composting which read, "Black Gold and the Power of One". These dedicated worm-lovers believe that if each person had a bin in his/her kitchen, the world would be a very different place. At least, everyone would have the perfect pets.

—Jane Stimpert White