"Worms do what!?!"
Yep, they eat my garbage! Worms transform our food scraps into rich, even-better-than-compost "vermicompost" – compost made by worms.
The first question people ask is, "Why do you do it?" There are many reasons. I have to admit that we think it’s fascinating and fun, but there are practical reasons as well. We have a garden and use the rich vermicompost to enrich the soil. It’s an important part of a healthy soil ecosystem.
In the winter, it’s an easy way to dispose of our food scraps without throwing them in the garbage or onto the frozen "regular" compost pile. Also, worms can handle food scraps that wouldn’t typically be added to a suburban or urban compost pile – things such as cooked foods or leftover pizza. It complements our "regular" compost bins, which we now use mainly for yard wastes.
Worm composting has other advantages as well. People who have produced compost in an outdoor compost bin are familiar with the routine of turning the compost so it will process faster (although if you’re patient, it’s not absolutely necessary.) When you compost with worms, the worms do the work.
Worm composting also fills the bill for apartment-dwellers who may want to produce compost for their houseplants or even for the plants on their apartment’s property. They also might just want to experience the fascinating process of transforming their food waste into rich compost – one of nature’s miracles.
How to begin
To begin worm composting, the first thing you need is worms. You can’t use just any worms and definitely not nightcrawlers or the earthworkers living in burrows in your garden. You need the worms known as red wrigglers (Eisenia foetida). We bought our worms over the internet, and we have been providing worms to other people ever since. Start with 1,000 worms, which is a pound. A thousand worms can process about 3½ pounds of food scraps a week. They’ll soon reproduce, and the population will self-regulate based on the amount of food they’re given.
Once you have worms, they’ll need a place to live. Plan on providing about one square foot of surface area for each pound of garbage you produce per week. You can buy commercial worm composting systems, of course, but they’re fairly expensive. We’ve found that simple plastic 14"x20"x8" (or deeper) storage containers have worked well. We have seven bins of worms, each of which consists of a plastic storage container stacked into another container, preferably one that is deeper. The top container has holes drilled in the bottom so that fluid can drain out into the lower container. I lay a sheet of black plastic on top of what is in the top bin because worms do not like light and I lay one of the storage container covers on the top but offset one or two inches so that air can reach the worms. Trust me, the worms won’t crawl out. In fact, if you put the cover on the bin the worms, being in total darkness, will crawl all over the bottom side of the cover and fall out when you remove the cover. So leave it offset.
Fill your containers about half-way with bedding. Bedding can be shredded newsprint, "regular" compost, shredded tree leaves, or a combination of any of these.
Worms need to be in a moist environment, so moisten the bedding. Most food scraps have a certain amount of moisture in them, so maintaining a moist environment isn’t difficult. Your bins will collect the "compost tea" that drains through the holes. This should be drained off occasionally and can be used to water your garden plants. If it accumulates for a long time this liquid may have a less than pleasant odor.
Worms do best when the room temperature is between 59º and 77º, but any temperature between 50º and 86º will do. Most basements fall within this temperature range. That is where we keep our worms.
Once you have worms and a place for them to live, start feeding them. You’ll be amazed at how many food scraps you produce in a week. We have produced a weekly average of about 10 pounds of fruit and vegetable peelings, coffee and tea grounds, eggshells, spoiled or moldy food from the refrigerator, and plate scrapings. The worms’ special favorites seem to be melon rinds and banana peels. I’ve read that they also like leftover chocolate, but who has "leftover chocolate"?
When I add food to the worm bins I wear a pair of rubber gloves. I take the cover off the bin, pull the black plastic sheet back half way, reach into one of the exposed corners and lift up the bedding and worms and add handfuls of scraps. I push the material I pulled up back over the new scraps and then do the same with the other corner. Pull the black plastic back over, put on the cover (offset), and wash off your gloves. It is recommended that you bury the food in this way so that you're less likely to get fruit flies. I have tried laying the food scraps on the top just under the black plastic but fruit flies seem to find and they can multiply quickly.
Worms will eat many things, but there are some things you should not give them: hot, spicy foods, highly acidic foods, citrus, onion and garlic. It’s best not to add meat products since they might cause odors, and for health reasons, don’t use pet feces. Of course, non-biodegradables won’t work. Interestingly, garden wastes, such as grass clippings, are not recommended since they would heat up and harm the worms.
As the composting process continues, the worms excrete castings – worm poop! Every three to six months, the concentration of castings relative to bedding increases so that it’s time to harvest the vermicompost and provide new, clean bedding.
Harvesting worm compost
Here is one method of separating the worms from the compost. The is done with less mess if you have not fed the worms for several weeks, thus reducing the amount of undigested food scraps in the bin. First, empty the worm bin into some other container. As I empty the bin I set aside undigested food (for example, the banana peels that have not yet disappeared) and any masses of worms I find. I empty the rest of the nice dark, wet, spongy stuff (worms and compost) into a large container. I use old driveway sealer containers. I rinse out the now empty worm bin and add some new bedding. [I use old ground leaves.] I put the undigested food and worms that I had set aside back in. I then put on top the worms and compost that had just been removed from the bin. The objective is to have the worms crawl down out of the compost and into the new bedding below (thus separating themselves from the finished compost). I leave the bin exposed to bright light (sunlight is great but indoor light works during the cold months) and wait several hours to allow the worms to migrate away from the top of the bin. I then scoop off the top layer of the compost into a container (another old driveway sealer container). When I start to find lots of worms as I am scooping out the compost, I wait a while (a few hours at least) for the worms to continue migrating down. I keep doing this until I am close to the top of the new bedding. [This may take a day or two.] I then mix everything up, shake the bin to level it, add some new food scraps, cover the surface with the piece of black plastic and I am done harvesting the vermicompost. I put the top back on the bin but offset an inch or two. I now have most of the worms in the worm bin with new food and bedding and much of the compost in a container ready to be taken out to the garden and used.
Here is another method:
After about four to six months of adding kitchen scraps to the worm bin, a lot of what is in the bin is dark, moist and spongy – the worm compost. Stop feeding the worms for several weeks before harvesting. Remove the cover and the black plastic sheet and expose the bin to light – since I am working in a dark cellar I use a lamp. The worms will head down, away from the light. Come back after a few hours and gently scrap off the top ¾ to 1 inch of worm castings, putting that material into a container. Repeat this several times a day until you have removed much of the material in the container or it seems the worms have no place left to go. Add some fresh moist bedding and some food scraps, put on the black plastic sheet and the cover (still offset an inch or two) and you are done, except for taking the worm compost out to your garden.
Larger scale operations
Vermicomposting isn’t just for the home. The EPA estimates that about 25% of our waste stream is yard and food waste. Large-scale vermicomposting is an ideal way to process these wastes, and some communities and businesses are doing just that.
Locally, Toad Hollow Farms is developing a vermicomposting facility to complement their existing composting operation. They’ll be selling the resulting "Worm Dirt" as premium compost in addition to their current product line, Toad Hollow Farms Natural Compost.
Can you think of any place that has more food thrown away than a school cafeteria? Some schools have successfully implemented vermicomposting, minimizing waste and saving money. A comprehensive how-to manual called The Worm Café: Mid-Scale Vermicomposting of Lunchroom Waste by Binet Payne can be ordered at www.wormwoman.com.
Worm composting around the world
Many countries around the world are serious about worm composting, both as a way of handling waste and as a way of creating important soil amendments. Here are just a few examples of what other countries are doing.
Vancouver, British Columbia’s Office of Urban Agriculture subsidizes worm bin kits and even provides workshops at the Vancouver Compost Demonstration Garden. Worm composting is an important part of their overall waste-reduction program.
An organization in India has helped more than 2,000 farmers and institutions switch from conventional chemicals to vermicompost. It has also developed methods to convert biodegradable industrial waste like pulp waste from paper mills into vermicompost. Three facilities are producing 30 tons of vermicompost each month from this type of waste.
Cuba, with reduced availability of imported fossil fuels, pesticides, and fertilizers, has made earthworms a key to their agricultural sustainability. Cubans have found that vermicompost performs better than protein for animals.
Japan has three 1,000 ton per month facilities that vermicompost the wastes from pulp and food processing companies. The sale of vermicompost and fish bait helps pay for these operations.
More than just a hobby
We think worm composting is fun, but it’s more than a hobby. It’s part of our stewardship of the earth. For us, it represents respect for natural processes and an appreciation of the need to care for the finite resources of the earth. Our 10 pounds of food scraps a week yields a yearly total of 500 pounds of material that is transformed into life-giving compost that enriches our soil instead of being added to landfills. There are about 178,000 households in Onondaga County. If just 1,000 of these households do the same, it would represent more than 200 tons a year! Perhaps you can be one of the thousand!
To learn more . . .
If you want to know more about vermicomposting, read the classic book on the subject, Worms Eat My Garbage by Mary Appelhof, otherwise known as "Worm Woman." The Onondaga County library system has multiple copies of this book, and it’s also for sale at Baltimore Woods. As a former biology teacher, Ms. Appelhof provides a lot of fascinating information on the process as well as a wealth of practical information. It can answer any question and solve any problem you might have.
Believe it or not, there is a multitude of websites on the subject as well. For example, Cornell has a website that has useful information. You’ll be able to find many others.
