By Collin Dunn, TreeHugger

What is vermicomposting? Why use worms?

Known also as worm compost, vermicast, worm castings, worm humus or worm manure, vermicompost is similar to plain compost, except that it uses worms in addition to microbes and bacteria to turn organic waste into a nutrient-rich fertilizer. Vermicompost, or vermiculture, most often uses two species of worms: Red Wigglers (Eisenia foetida) or Red Earthworms (Lumbricus rubellus), which are rarely found in soil and are adapted to the special conditions in rotting vegetation, compost and manure piles.

How does vermicomposting work?
It works like this: after procuring a container and setting it up (more on that in a moment), feed your worms the same organic waste you’d toss in a compost pile — which includes just about all of your food waste (but hold the animal leftovers). They chew on it for awhile, and when they’re all done eating, they excrete nutrient-rich fertilizer.

Benefits of vermicomposting
In addition to increased nutrient levels, worm castings contain millions of microbes which help break down nutrients already present in the soil into available plant forms. As the worms deposit their castings, their mucous is a beneficial component absent from compost produced by hot or cold composting. The mucous component slows the release of nutrients preventing them from washing away with the first watering. Worm compost is usually too rich for use alone as a seed starter. It is useful as a top dressing and as an addition to potting mixes at a rate of one part castings to four parts mix. Your plants will love it.

Using vermicomposting bins
Unlike compost, which can work its magic in a pile in your backyard, vermicompost requires a bit more structure to work, usually in the form of a bin. Bins can be made out of just about anything, but they require drainage and air flow to be built in, so things like styrofoam (very insulating, and may release toxins into the worms’ environment) and metal (too conductive of heat and cold) are generally less desirable, and plastic requires more drainage than wood be it can’t absorb moisture. The design of a bin usually depends on where you want to store the bin and how you wish to feed the worms.

Most small bins can be grouped into three different groups; keep reading to learn more about the three categories of vermicomposting bins, and how to get started with vermicomposting.