Composting is the process of converting food scraps and/or lawn waste into fertile soil. Many people compost outdoors either in an open pile or closed bin. While this can work well for some, there is definitely a noticeable odor that the neighbors might not approve of if they happen to be downwind. It can also be a hassle to bring food scraps outside, especially during northern winters. An alternative to this is the use of worm composting, or "vermicomposting."

With vermicomposting it is possible to bring composting indoors, making it accessible to a greater number of people, including apartment dwellers. I've been keeping a "worm bin" in my kitchen for a few months now. It's a plastic tub with holes drilled in the top (for air) and bottom (for drainage) filled with dirt and "red wriggler" worms. Instead of throwing food scraps into the trash, I bury them in the worm bin, and the worms convert them into "worm castings." The result is a rich soil that my garden loves, and I don't need to take out the garbage quite so often.

As long as the food scraps are buried and you have enough worms, there is no odor. If an odor develops, simply stop feeding the worms for a few days until they catch up. As your well-fed worms reproduce the bin will be able to handle a larger amount of scraps. Chopping up vegetable peelings into smaller pieces also helps speed along the process. In general, worms can convert about half of their own weight in food scraps each day into compost.

It is not difficult to make your own worm bin. All that is needed is a container that lets air in and keeps the worms inside. While it's possible to build one from wood, I've had excellent luck with the plastic bin with holes drilled in the top and bottom. Mesh over the bottom holes keeps worms from accidentally crawling out. If that sounds too ambitious, search for "vermicomposter" online to find many companies selling pre-made worm bins.

Worms for worm bins can be purchased at bait shops or from retailers that sell vermicomposters. You need to use worms that are suited for this task, generally either brandling worms (Eisenia foetida) or redworms (Lumbricus rubellus) which are also known as "red wrigglers." The common earthworms you find in your yard will not work, as they prefer plain dirt to your kitchen scraps. The bin should be filled with moist bedding made from paper, leaves, straw, or peat moss before adding food scraps for the first time.

You can feed your worms any biodegradable garbage, including tea bags, eggshells, coffee grounds, and paper towels. It's best to avoid greasy or oily foods, spicy foods, meat, too many citrus peelings, or paper with colored ink.

Vermicomposting is a great activity to do with children. It teaches them about biology, soil, and conservation while encouraging them to be more responsible about garbage and recycling. Many schools have implemented vermicomposting projects, and they are generally very popular with students.

The links below provide further information about vermicomposting. Worms may not be as lovable as a loyal dog, but they can make a great addition to your home.

Resources:

Vermicomposting Guide from New Mexico State University  (cached)
a good basic guide to vermicomposting. You will need the Acrobat Reader to view this file.

Book: Worms Eat My Garbage: How to Set Up & Maintain a Worm Composting System
this excellent in-depth guide to vermicomposting has encouraged thousands to compost with worms.

The Adventures of Herman
a site designed for kids that has excellent educational information on worms as well as how to set up and take care of a worm bin.

Worm Composting at Portland Public Schools  (cached)
this page explains how worm composting has been used in one public school system to cut back on cafeteria garbage and teach students about nature's cycles.

Worm Bin Project  (cached)
a lesson plan for implementing a worm bin project to students.