A Beginner's Guide to Vermicomposting

CGEE Student Voice
by Jenni Abere
The majority of cities in the U.S. don’t yet have organics composting collection— but that doesn’t mean you can’t start reducing your waste footprint! While you’re waiting for your city to get on board with organics, you can start composting at home.
Vermicomposting is composting using worms. This can be done indoors in a relatively small bin. The start-up cost is low, and it’s easy to maintain. Plus, it produces the most nutrient-rich soil you can get.
Here’s how to get started:

1. Get a bin.

There are bins made for vermicomposting, but you don’t need anything special. I used a medium-sized rubbermaid bin from Target. When looking for a bin, you want one with more surface area, so a shallow and large bin is best. Worms can be harmed by exposure to light, so make sure the bin has opaque sides.

The bin can sit in a closet or room where it won't be disturbed often. 

2. Set up the bin.

Worms need to breathe, so drill some holes in the sides and lid. To control moisture, you can drill a few holes in the bottom. This will require something to catch excess moisture. I simply bought a larger bin to nest the smaller bin inside of.

3. Add bedding and food.

These are the two materials that you will need to continually add to any composting bin, including a worm bin. They go by a lot of names: bedding and food, browns and greens, carbon and nitrogen. Essentially, bedding is something that used to be alive, and food is still alive.
Bedding is dry and fibrous so it will absorb moisture, and hold the soil together. I use shredded newspaper, and non-recyclable paper like toilet paper tubes and egg cartons. You can also use dry leaves or straw. You want about twice as much bedding as food.
Now for food. Worms aren’t very picky, but there are some things they can’t eat. Firstly, they are vegetarians! Don’t put any meat or dairy in your worm bin. The best food is raw fruit and vegetables. Worms are the perfect solution to non-preventable food waste such as banana peels, apple cores, and other peels, stems, rinds, and skins. They also like tea bags and coffee grounds— including the filter!

My worm bin feat: shredded toilet paper tubes and tomatillo husks. 

Avoid processed, cooked, and oily foods. Worms can handle small amounts of starches, citrus, and onion. In a small indoor bin, you may want to avoid these foods altogether.

4. Add the worms!

Set up your bin a week or so in advance so the food begins to decay. Before adding the worms, make sure the bin has an appropriate moisture level. It should feel like a wrung-out sponge. Adding food will increase moisture, and bedding will soak up excess moisture. Make sure the bin is aerated properly; adding dry bedding will help.
There are many places to order worms online. The type of worm you want is called a red wiggler or red worm. You can plan for about 1,000 worms (or one pound) per square foot of your bin, but aim low when first ordering. They will multiply quickly if conditions are right. You don’t have to worry about having too many worms, though: If they run out of space and food, they will reproduce at a slower rate.
Worms may try to escape the bin when you first add them. They are restless from travel and not accustomed to the new bin. Give them some time to settle down, but be prepared to scrape some dried up worms off your floor.

5. Harvest the compost.

It shouldn’t be long before you see dark, rich soil in your bin. You need to remove finished compost every few months to keep the worm bin healthy.

No inputs are recognizable in finished compost.

Several weeks before you plan to harvest, only add food to one half of the bin. This will draw the worms over to one side. Then simply dig to the bottom of the bin and pull out the dirt. I pick out worms and bits of food/bedding that isn’t completely broken down yet, but this can become a painstaking process. A few worms and scraps aren’t going to hurt plants.
After you’ve harvested, now you have a pile of rich, moist soil. If you’re an apartment dweller you may not have a use for so much soil. What now?
Remember that you’ve got a valuable commodity here! Ask friends and family if they would like some for their yard. Otherwise, go to a public park and sprinkle some in the grass and around trees. If it’s the middle of winter this might not be possible. You can store the compost by keeping it moist.
Composting is valuable as a way to reduce waste, so don’t worry if you don’t have a good use for the end-product!

This basic information should help you get started, but any other questions can be answered online! There is a surprisingly large community of vermicomposters online to share tips and help troubleshoot.