Do it Yourself Worm Farm
- You can build a do it yourself worm farm from a single container, or create a more complex system of three bins that you rotate as the worms move up in the soil. Plastic bins are the cheapest and easiest container to use for a worm farm. Use sturdy, solid-color opaque bins---worms like darkness. The bedding should be no deeper than 18 inches, so 20 to 24-inch tall bins are appropriate. Place one lid or a drainage bin under your worm farm to catch the "worm tea" liquid by-product of the worm activity. Be sure to obtain a solid lid with your container, to make the surface dark and keep moisture in.
Drill several drainage holes in the bottom of the bin(s). Drill ventilation holes an inch or so from the bottom of the sides as well as holes along the sides at the surface of the bedding. Cover the side holes with screening to allow air in but to keep the material from spilling out. Drill two holes in the lid of the bin to allow air circulation. Screen these to filter light as much as possible.
Shred newspaper for bedding, into 1-inch strips or smaller. Wet the newspaper and squeeze the water out until only a few drops form. Layer this moist bedding with a small handful of dirt or sand for grit---this helps the worms "chew" their food. You will be burying your food waste within this bedding material for the worms to eat. The worms will eat the newsprint too; the black ink used in newsprint is safe for worms but avoid the slick colored ads. You can use leaf litter as well but this may bring in unwanted insects such as gnats if the worm farm is to be kept indoors. Manure is a good bedding material but may have an unpleasant odor when moistened.
Out of 3,000 species of earthworm, Eisenia foetida, the redworm, is the best worm to use for shallow container worm farming. Common names for redworms include "red wiggler," "manure worm," "dungworm," "red hybrid" and "striped worm." You might think that larger worms would eat faster and produce more castings, but nightcrawlers are a deep-burrowing species, unhappy in a shallow container, and most garden earthworms are soil worms, happiest in plain dirt. Eisenia foetida thrives on large volumes of organic material within 18 inches of the surface, making them the perfect candidate for this type of farming. - Redworms will eat just about any organic material; however, for best results you want to avoid highly acidic food wastes, dairy products and meat. Worms like vegetables, fruits, coffee grounds, cereals and crushed eggshells. Bury your food waste in the bedding to avoid growing fruit flies or attracting houseflies.
Don't overfeed your worms. Experts at the Whatcom County Extension Office, Washington State University, recommend a ratio of 1 pound of food for every 2 pounds of earthworms per day. If you have more food waste for them than that (use a scale for accuracy), store the extra in the refrigerator until your worms are ready for it. If you've accidentally overfed them, don't worry---simply stop feeding them fresh food until they've caught up. - Redworms need temperatures between 55 and 77 degrees Fahrenheit. Plan to keep your worm farm insulated from freezing temperatures and protected from temperatures above optimum. Keep a thermometer inside your worm farm to monitor the temperature.
Get a hand rake for stirring the bedding, to introduce air. You want an aerobic environment for the worms or the decomposing material may begin to stink. As you turn the material over 4 to 6 months, you will note the food you put in is becoming small black crumbles---this is the worm castings. For single-bin systems, scoot this used bedding to one side and place fresh bedding in the other side. Bury new food in the new bedding. The worms will continue to process the old bedding until there is no more food left; at that point, you may harvest your crop of castings. Multi-story bin systems allow the worms to crawl upward into new bedding and food, leaving their discarded castings in the bottom layer for you to harvest.
