Make Your Own Worm Bin

By Celine Rich-Darley
Category: Gardening, Home
Difficulty: Moderate

For three years I lived in a house with an outdoor composter. Then my family moved to an apartment in San Francisco where there was neither composter nor green box pickup! What was I going to do with all my kitchen scraps? I didn’t have the heart to put them in the landfill garbage or down the garb-o-rator.

According to the EPA, in 2007 organic-based materials continued to be the largest component of municipal garbage in America: 33% was paper and cardboard, and 25% was yard trimmings and food scraps. I could put my paper and cardboard in the recycling bin, but without a yard, how could I recycle my apple cores, cabbage trimmings, and eggshells? Then I remembered worms.

Worm composters are great for apartments. No matter the climate or the size of your home, vermicomposting is good for you. Well, good for your plants. If you have children, there’s the added advantage that most kids love worms (it’s genetic), despite the fact that they’re not very cuddly or furry.

My 4-year-old son is fascinated by worms: from our outdoor composter he’d already learned that worms turn kitchen scraps into soil as if by magic.

Soil is extraordinary stuff, and despite the fact that it’s as vital as water, it’s still not fully understood by scientists. But we do know that we’re losing soil to erosion and runoff, and that composting can help restore soil, save landfill space, and reduce greenhouse gas emissions.

Worm composters are simple to build and easy to manage. Your worms can convert 5–6 pounds of food scraps a week into 10–15 gallons of compost a year.

Worm compost and worm tea (the drippings that collect in a tray at the bottom of the composter) can be used to fertilize both indoor and garden plants. Worm compost is higher in nutrient value than regular garden compost.

I’m looking forward to happy plants and less waste in my garbage cans, and so can you!

Steps

Step #1: Make drainage holes.

In the bottom of the plastic box, drill about 20–25 evenly spaced ¼" holes.

Conclusion

Worm Facts

The best worms for vermiculture (worm composting) are Eisenia fetida (striped) or their cousins Eisenia andrei (not so striped), aka redworms, red wigglers, tiger worms, or manure worms.

Worms need grit for their gizzards to grind up and digest food, because they have no teeth.

Worms need a moist environment because they breathe through their skin, which must be moist in order to breathe.

Worms can eat about half their weight every day. Therefore, if you produce ½lb of kitchen scraps a day you’ll need 1lb of worms. There are about 500 worms in a pound.

Worms hate the light.

Ideally worms like the temperature to be between 55°–77°F (13°–25°C). However, they can tolerate 40°–80° F. If they get too hot or cold, their activity slows down. Try not to kill your worms! Protect them from overheating (above 85°F in their box) or freezing.

Worms need oxygen to live and they produce carbon dioxide. Your composter needs to be in a well-ventilated area.

Worm castings (worm poop) are toxic to your worms. That’s why it’s important to regularly harvest your compost.

Worms are great barometers. Before and during any low-pressure system such as a thunderstorm, worms like to crawl up and around the lid of the worm composter.

The Redworm Life Cycle

Worms can live less than a year if their environment is not ideal. However, Eisenia fetida (striped worms) can live as long as 4 years.

Worms are hermaphroditic but mating is still necessary. Worms mate anywhere in the box and at any time of year if moisture and temperature conditions are right.

Before mating, a part of the worm called the clitellum, located about of ⅓ the way down the body, will swell to form a cocoon filled with eggs. A worm’s sex organs are very close to the clitellum.

Worms mate by lying side-by-side with their heads in opposite directions, so that the sex organs line up with the clitellum. Sperm from each worm moves down a groove into the receiving pouches of the other worm.

After the worms have separated, the clitellum secretes a substance called albumin. This material forms the cocoon in which the eggs are fertilized and baby worms hatch.

Redworm cocoons are small and round. They change color during their development: white, then yellow, then brown, then finally, when new worms are ready to emerge, red.

Incubation in the cocoon is between 32 and 73 days. Temperature and other conditions affect the development of the hatchlings. Although a cocoon might hold as many as 20 eggs, usually only 3 or 4 worms will emerge.

The young hatchlings are whitish with a pink tinge, which shows their blood vessels.

In about 8–10 weeks the baby worms will be mature and can begin reproducing. If conditions are good, a mature worm can make 2–3 cocoons per week for 6–12 months.

More information about vermiculture can be found at http://ciwmb.ca.gov/organics/worms.

This project first appeared in MAKE Volume 18, page 78.