How to Raise Earthworms for Composting

Wash out a large container to keep your worms in. An old dresser drawer, bin or any container with a depth between 8 and 12 inches will work. Deeper containers may lead to a smelly worm bin because of compacted food and bedding.

Place your bin in a shady location where it won't freeze or overheat. A corner in the kitchen, garage, basement, patio, behind the back door or laundry room all work well. Red worms prefer temperatures between 55 and 77 degrees Fahrenheit, according to the Arizona Cooperative Extension. Place the bin on bricks or wooden blocks over a metal tray or plastic sheet to catch any bin contents and ensure air circulation.

Create bedding for your earthworms, where they'll live. Shred, rip, cut and tear a variety of items in different sizes, including leaves, newspaper, office paper, cardboard, peat moss and almost-cooked compost.

Apply a thick layer of moist -- not wet -- worm bedding, about three-quarters of your bin depth. Red worms need constant moisture, as they absorb it through their skin, but too much moisture causes anaerobic conditions, depriving the worms of oxygen. The moisture level should be about the same as a wrung-out sponge.

Stock your bin with kitchen scraps such as apple cores, rotten greens or banana peel. The worms eat the microorganisms that break down food. Cut food into small chunks so it decomposes quicker, and the worms can eat faster. Do not blend food. Watermelon and cantaloupe rinds, rinsed corn cobs, pumpkin, coffee grounds, veggies, tea bags, fruit and egg shells all work well. The worms will tolerate garlic, onion and citrus. Spread the food in a layer atop the bedding until you have about 2 to 4 inches of space at the top.

Keep the inside of the container very dark with a tight lid. Worms will die after too many hours in the sun.

Drill about 20 1/16-inch breathing holes on the bottom of the bin of the bin and several on the sides, well above the bed line and the lid. This helps keep oxygen in the bin without drying it out.

Purchase your earthworms. Red worms like Eisenia foetida or Lumbricus rubellis, not nightcrawlers or worms you'd find in the garden, can live in a worm bin. Carefully place them in the prepared bedding with food already in it. Worms eat microorganisms feeding on the food, so a prepared bin complete with food keeps them from trying to escape to look for other food sources.

Add food to your bin consistently to keep your worms healthy.

Collect your finished compost twice a year to keep a healthy worm population. Move the bin contents to one side, clearing a small area. Place fresh bedding and food here. Harvest the compost on the opposite side in a month or so, when the worms have migrated to the new food and bedding.