What is Vermicomposting?
Vermi is Latin for worm, so vermicomposting is simply the decomposition of plant materials by worms. Worms consume the kitchen scraps that you feed them, and release castings (worm droppings), also called vermicompost. This is recycling at its best, transforming waste into a valuable resource for your garden. Vermicompost not only feeds plants, but it improves your soil’s texture, and may provide some protection against certain pests. It’s superior to traditional compost in several ways. “Vermicompost has higher nutrient concentrations than compost but lesser amounts of soluble salts,” explains Rhonda Sherman, director of the Compost Learning Lab and Extension Solid Waste Specialist at North Carolina State University. “Vermicompost has more nitrogen than compost because hot composting releases more nitrogen into the atmosphere. Vermicompost has lower carbon-to-nitrogen ratios than compost, which makes nutrients more available to plants,” she adds.
How to Compost with Worms
One of the best features of worm composting is that it can be done in a small space right in your own home. It can also be done outdoors. All it takes is a bin, some bedding, a bunch of worms, a steady supply of food scraps, and a little time. The worms do all the hard work. Use these steps to set up your worm bin.
What to Feed Composting Worms
Worms may consume 25 to 35% of their body weight in one day depending on the conditions in your bin. Feed your pet worms vegetable and fruit scraps (they really like cantaloupe, pumpkin, and watermelon), used coffee grounds and tea bags, crushed egg shells, and shredded garden waste. Avoid citrus scraps, which can be too acidic, and never give them meat, fish, or salty or greasy foods. Start feeding your worms slowly—give them no more than an inch of food scraps to start—and use a small garden fork to cover the food with an inch or two of bedding. A pound of red wigglers can go through two pounds of food scraps in one week, but don’t overfeed them or your bin may start to smell. Wait until the scraps from your previous feeding have disappeared before offering the next meal.
Harvesting Vermicompost
“The earthworms will excrete castings that accumulate on the bottom of the worm bin,” explains Sherman, who notes that most people begin harvesting the vermicompost after four to six months. To do so, you can feed the worms on only one side of your bin for a few weeks. Most of the worms will move to that side so you can remove the vermicompost from the other side. Then do the same thing on the other side. Use a soil and compost sifter to separate out any larger pieces that still need more composting time. Another harvest option is to empty the contents of the bin onto a large piece of plastic sheeting or a waterproof tarp in bright sun or artificial light. The worms move away from the light, so after about five minutes, scrape off the top layer of vermicompost. Repeat at five minute intervals until you see lots of worms. You can then put them back in the bin with fresh bedding to start the process again. Vermicomposting is a fascinating activity the whole family can enjoy, and your garden will too. Besides creating a super nutritious garden supplement, vermicomposting reduces the amount of food waste that is hauled to the landfill. A win-win for all (including the worms!).
