Down the Garden Path: Worming your way into composting

Composting is a win-win for both you and the environment. Recycling food waste gives you a nutrient-rich soil amendment for your lawn and garden. Composting also saves landfill space and reduces methane production, a greenhouse gas.

You may be familiar with composting outdoors using a bin or pile. But what if you don’t have space or your community doesn’t allow outdoor composting? You can compost indoors using worms! Called “vermicomposting,” this can become a fun family project.

Choosing which wigglers

The red wiggler (Eisenia fetida), used for indoor composting, is a warm-weather European earthworm. They process about half of their body weight in a day, so one pound of worms can eat about a half pound of food daily, which is about 2-3 carrots worth of scraps. Red wigglers can be purchased from suppliers locally or online.

Creating a moist, dark home

Like all earthworms, red wigglers breathe through their skin, which needs to be moist for this to happen. They also live close to the surface, prefer warmth, and avoid light. Premade bins can be purchased, or you can easily create a successful habitat for your worms using a plastic storage bin with a lid.

Start with a 10-gallon bin, which can support ½-1 lb of worms. Drill 2 rows of ventilation holes along the sides of the bin and in the lid using a 1/8” bit.

Fill the bin with newspaper strips about 1 inch wide. Wet the newspaper so it is moist, like a wrung-out sponge. Then fluff the wet newspaper so it isn’t packed down. Worms will eat paper, so you will occasionally need to add more.

Sprinkle a handful of soil into the bin. This adds microorganisms and grit that will help the worms process their food.

Now add your worms to the top of the newspaper and watch them burrow away from the light. Don’t worry; they will not escape from the ventilation holes if you keep them moist, and well-fed.

Feeding your worms

Your worms will eat a variety of soft, non-oily food scraps, including fruit and vegetable peels, pasta, bread, and coffee grounds. The smaller the pieces, the faster the worms will eat them. To feed, bury a handful of food scraps 3-4” under the newspaper. Check every few days to see how fast they are eating. To avoid bad odors, only add food when they have eaten what you gave them, and don’t feed foods that can become smelly such as onions, fish, dairy products or meat.

Harvesting worm compost

In a few months, worm compost (castings) will build up on the bottom of the bin. You can harvest castings by “dividing and sorting.” Push all the material, including the worms, to one side and stop feeding for 2 weeks. Then, add fresh, dampened newspaper with buried food to the empty side. Within a short time, your worms will move into the new bedding, and you can harvest the finished compost on the other side. Refill the harvested side with fresh, dampened newspaper with more buried food.

Using worm compost

Worm compost is higher in nutrients than compost made in bins or piles, so use a small amount. Scatter a few tablespoons onto the soil of potted plants as a fertilizer or sprinkle a handful around the base of your garden plants.

Try this fun project and create something useful from waste while helping the environment.

For more information, see go the the University of Illinois Extension page here.

• Sue Styer is a certified Master Gardener and Master Naturalist volunteer with the University of Illinois Extension, serving DuPage, Kane, and Kendall counties.