Do you have worms?This may not sound like polite conversation, but if you’re a gardener or a composting enthusiast, you’ll likely give a happy and affirmative answer to this question. Along with other invertebrates that eat decaying plants, earthworms are extraordinarily helpful garden animals. They turn those old plants into soil, helping to liberate nutrients that once again enrich your garden.
Want a garden that’s bursting with life? It’s all in the soil. Photo: Oakley Originals / CC by 2.0
If you live in an apartment or in a place where outdoor composting is not allowed, you might wish for a bit of rich, dark compost to help make your patio plants healthy. You may also want to reduce your waste stream, turning vegetable and fruit scraps into soil. If it just doesn’t make sense to you to throw out those important nutrients, read on to find out how you can turn food scraps into soil using an indoor composting system called a worm bin or worm compost.
How do you make an indoor worm bin? It’s pretty simple!
You Will Need:
- 1-2 bins. I like plastic storage bins. It doesn’t matter what you use, but it needs to be the right size for the vegetable waste you produce, lightweight, nontoxic, and waterproof.
- Electric drill
- 1/4 inch drill bit
- Eye protection
- Shredded newspaper, coir, cardboard
- Handful of sand
- Scale (if desired)
- A warm, sheltered deck or secure indoor location for your bin
A typical worm bin full of bedding and soil. Photo: jeffschuler / CC by 2.0
How Big Should My Bin Be?
How much food waste do you produce? Count fruit and vegetable scraps, but don’t count meat, dairy, and bread. These should not go into your bin. An average family of 4-6 will need a bin that’s about 1′ by 2′ by 3′. This bin can handle about 6 pounds of waste per week. If you create less, you will need a smaller bin. If you create more consistently, get another bin. If you create more vegetable waste in the summer months when fresh vegetables are plentiful, consider spreading out the waste between two bins. Make sure that your bin is as wide as a typical storage bin. Very tall, thin bins don’t get a lot of oxygen down low, and worms like to feed at the surface of the bin, so the more surface, the better.
What Do I Do With the Bin Once I Have It?
Once you have your bin, it’s time to get it ready for your worms. I like to drill 1/4 inch holes in the lid and the sides. I put them several inches apart. This is to ensure that air can flow through the bin. I also drill holes in the bottom of the bin so that any excess liquid will drain from the bottom of the bin. I prefer to buy two bins, so that one can slip inside the other. The second bin catches the liquid and I can use it on the garden.
What Should I Put In the Bin?
Before you put in your worms, put in some bedding. I like to start with a layer of coconut coir, an eco-friendly alternative to peat. Then I cover it with well-shredded newspaper. I tuck food waste under the newspaper so that the flies don’t get at it. When I first put in the forms, I add a handful of sand, since worms need grit. I also spray the paper gently with a spray bottle to get it moist but not wet. I don’t do this every time, but I want the new worms to go into a moist environment.
Yes, you have worms. Photo: jeffschuler / CC by 2.0
How Many Worms Do I Need?
While many composting systems use worms, the containers that you use outdoors rely on your local worms to colonize them. They also rely on on other organisms such as fungi and bacteria. Indoors, you’ll need to buy the worms that you place in your compost bin. Don’t collect worms from your garden. You need red wrigglers or red worms that enjoy feeding off fresh decaying plants near the top of the soil layer. The number of worms you need depends on the amount of food waste you produce. 2 pounds of worms can eat about a pound of food. Do a web search in your area, and you’ll likely find a lot of people who sell their excess worms for profit!
Now You’re Composting!
Once you’ve tucked your worms into the bin under the bedding, with a bit of food to get them started, you’re composting! Place your bin in a sheltered location with a stable temperature. For the first week or so, your worms will need to get used to their new environment so they may eat a little less. Soon you’ll see your bedding and food scraps turn to rich, dark, soil. Remember to add new bedding on top of the food waste as the worms munch it, stay within your daily limit for waste per bin (1 lb/2lbs of worms), and make sure that your bin is at a good temperature and moisture level. Overall, worms make very easy care animals, and they’ll add to your garden and reduce your waste bill at the same time.
