from the garden of Beth DiGioia, The Art of Living Beautifully Resident Gardener
Vermiculture (The Cultivation of Worms) : AKA Keeping your Little Students Busy Over the Holiday
Your little students are soon home from school and you may be searching for ideas of how to keep them busy in a productive way. Well, consider constructing a worm composting bin as a family project and then they can care for it over the Holiday. It’s easy and fun, and it doesn’t have the ick factor that the name implies.
Most of us are familiar with composting: kitchen scraps such as fruits and vegetables, coffee grounds, tea leaves, eggshells, bread and cereals are layered in an intricate ratio with yard waste (grass, leaves and garden clippings). The pile is turned on a regular basis and heated to a certain temperature. Oh my! Trust me, vermiculture isn’t as complicated as composting. And it can be done in the warmth of your laundry room or garage – no trudging down to the back forty to deposit a bucket of scraps into a bin every day. What it does have in common with composting is the list of foods not to put in the bin: meat, dairy, fat, citrus, moldy food, diseased plants or pet wastes.
I love that I can convert organic waste that would end up in the landfill into nutrient-rich earth worm castings that I would willingly pay big bucks for at the garden center. Plus, worms are quiet, don’t smell and reduce my carbon footprint.
Want to give it a try? Cultivating worms is basically a system of four interdependent parts:
- The physical structure (box or container)
- The worms
- The environment (temperature, moisture and ventilation)
- The procedures (preparing the bedding, burying the food scraps and harvesting the castings)
The size of the box or container depends on the space you have available and the amount of kitchen waste you have. The ideal container is shallow, usually no more than 12-18” deep because worms nibble from beneath the material on the surface. Containers must have holes drilled in the sides and top to allow for ventilation. The material the container is made of doesn’t matter as long as it is at least 12” deep. Wooden boxes and small galvanized garbage cans are popular; my container is a large Rubbermaid plastic bin. If you choose a plastic container, scrub it with hot water and soap and rinse well to remove any chemical residue from the plastic.
Not all worms are the same and it’s important to use the right kind of worms in your home vermicomposting system. You want a worm that processes large amounts of organic material (food scraps) and that reproduce quickly in confinement. Most of the worms that you would dig up in the garden are not suitable. Red worms (aka red wigglers) are the best for vermicomposting. To make sure you are getting the correct worm, order them by their botanical name Eisenia fetida. Other suitable worms are Eisenia andrei and Lumbricus rubellus. Worms are sold by weight and the general recommendation is a worm:food scraps ratio of 2:1. If you feel you’ll be burying an average of one half pound of food scraps a day, start with one pound of worms.
Red worms feed most rapidly and convert waste best at temperatures between 59-77 degrees. Worms breathe through their skin, which must be moist for the exchange of air and excretion of waste (castings) to take place. Add water to dry bedding when necessary, but don’t allow water to stand in the bin because too much moisture can reduce oxygen and cause worms to drown. Worms use oxygen just as we do, so ventilation is important.
The most desirable beddings are light and fluffy. The least expensive and most readily available bedding is newspaper (black ink only) or other paper that has been run through a shredder. Shredded coir (coconut fiber) is another clean bedding as long as it represents only one half of the total bedding. Adding a handful of soil when preparing the bedding will provide some grit to aid in breaking down food particles within the worm’s gizzard. Other sources of grit are rock dust and zeolite.
To set up the vermicomposting container:
- Choose your container and drill holes around the upper quarter on the sides and in the top.
- Fill it about three quarters full of moistened bedding.
- Add the worms and gently spread them out. Leave the top off the container so that they will move down into the bedding to avoid the light.
- After an hour, you can start feeding the worms. To do that, push aside some of the bedding, bury the food scraps and then cover it completely with the bedding.
To maintain the vermicomposting system, add food scraps when they’re available and cover it with bedding. If the bedding starts to break down, add more. If the bedding seems dry (the bedding should have the moisture content of a wrung out sponge), add a little water.
In two to three months you will be ready to harvest the nutrient rich earth worm castings. The easiest method is to spread a plastic sheet in the grass and dump the entire contents of the bin onto the sheet. Make eight or nine piles. The worms will react to the light and move toward the center of each pile. Leave the piles alone for about ten minutes and then gently remove the outer surface of each pile. The worms will again react to the light and retreat to the interior. Repeat the procedure. Eventually the worms will be in a mass at the bottom of each pile. Add these worms to fresh bedding and you’re good to go again.
I hope that your family enjoys this project! I know your garden will benefit from the addition of the worm castings.
For more of Beth’s gardening articles, visit our McKinney Gardens page.