Friday, September 12, 2008
(image from redwrigglerranch)
More accurately, my new best friends are 2,000 worms! I started vermicomposting after seeing an Oprah show about going green. The show offered various ways you can “green” your home including getting a worm bin. The worm segment made Oprah so squeamish she recommended, “leaving that to the professionals”. Unlike Oprah, I was fascinated by the worms and decided to look into vermicomposting as a good way to deal with my food wastes.
Vermicomposting is all about using composting worms to create vermicompost, or worm castings, which is an incredibly nutrient rich organic fertilizer and soil conditioner. In other words, you take what you were going to throw away, feed it to some worms and end up with the best fertilizer around. What could be better than that?
I decided to purchase a Worm Factory, but you can easily make your own. There are lots and lots of instructions on the Internet for various homemade worm bins but the simplest ones involve a Rubbermaid storage bin with holes drilled in it for aeration. Google “worm bins” and you’ll see how easy it is. There are lots of videos on YouTube as well. Once you have your worm bin, you will have to decide where to put it. Your worms can overheat and die so do not put your worm bin in the sun. If you are going to keep your worm bin outside, find a shady spot. The top safe temperature for the bin is about 85°. Since I live in a hot climate and was using a black plastic bin I was concerned about the temperature, made what may seem like a bold choice and decided to keep my bin indoors. I have a basement and chose to put it down there. In case you are cringing, let me tell you that a well-functioning worm bin does not smell at all. If I didn’t have a basement I would have no qualms about putting it anywhere else in my house where it wasn’t in the way.
Your worms will need some bedding. I use shredded junk mail and cut up cardboard boxes, which keeps them out of the landfill, too. If you are using shredded junk mail, be sure not to include any glossy paper. I derive a certain satisfaction from feeding political fundraising requests to my worms! Other good bedding materials include shredded newspaper, aged straw and rotting leaves. Coconut coir makes an excellent bedding material but unless you have a supply available to you, you will have to purchase it and that’s really not necessary. Next, you need to wet down the bedding. A common rule of thumb is to dampen your bedding to the level of a wrung-out sponge. Fill the bottom of your bin with about 3-4” of damp bedding. Now add some food to your bin.
Worm food consists of any sort of vegetable waste plus things like coffee grounds and tea bags. One exception is citrus scraps. The acids in citrus peels make them unpalatable to the worms. I think they actually burn the tender worm skin. You will also want to avoid onions and garlic. Do not add any meat scraps, dairy products, oils or grease. The worms don’t like these materials and they will simply rot, smell bad and attract pests. You will want to cut your vegetable scraps into small pieces for quicker worm consumption. I try to cut my scraps into roughly ¼" cubes. Larger scraps will certainly be consumed but the smaller the wastes, the faster the worms will process them. One source I came across suggested running your scraps through the blender or food processor. That would work really well but personally, I did not want to continuously clean my blender and so opted not to follow that particular tip. Freezing your scraps will kill fruit fly eggs. Fruit flies can be a problem and, as I have ample freezer space, I keep all my worm food scraps in the freezer until I use them. I add the frozen scraps directly to the bin and have had no problem with that approach. Worms, since they have no teeth, need a little grit in their craw to process the food scraps. Ground-up eggshells serve this purpose very well. Bentley, over at Red Worm Composting, suggests putting your bin, bedding and food scraps together and letting them sit for a week or two before adding the worms so as to create the most convivial atmosphere for the worms when they first arrive.
Next, add your worms! Composting worms are not standard earthworms. You can’t go out in the backyard, dig up some worms, throw them in your bin and expect a good result. You need red worms, Eisenia fetida. There are other varieties of composting worms but red worms are the most common. The difference is that earthworms are burrowing worms that dig down in the soil and need to have a little room. Composting worms live more at the surface, in rich organic material, not dirt, and are happy all crowded together. You can order the worms online from several sources and they will be shipped through the mail. A common formula for figuring out how many worms you need is to add one pound of worms for each square foot of bin surface area you have. I bought two pounds of worms for my five-layer Worm Factory. One or two pounds will work pretty well for a home, kitchen-waste type of system. Happy worms multiply fairly quickly. They are not cheap so you might want to buy a pound and see how it goes. Until they are settled in their new home, your worms may want to go traveling! Luckily, worms are sensitive to light. You can counteract their tendency to run by leaving the lid off your bin and leaving a light on for a few days. The possibility of a “B” movie playing out in my basement caused me some consternation at first but I left the lights on down there for 3 or 4 days and never had a problem.
Happy red worms will reportedly consume about ½ their body weight each day. I’m not sure mine are eating that much but they do eat a lot of vegetable scraps, which are no longer going in the trash. This post is by no means a comprehensive resource for vermicomposting. There is a lot of good information out there. My favorite source is Red Worm Composting. Bentley seems to know just about everything there is to know on this topic and will readily respond to reader questions. He has a newsletter and hosts worm forums on his site. If you are thinking of starting a worm bin, which I highly recommend, check out his website.
The production of vermicompost is not a quick process. Plan on at least three months, based on the size of your bin and number of worms, to get your first batch. The beauty of a stacking system, like the Worm Factory, is that as the worms finish one tray, you add another and the worms move up. By the time I get to the top tray I should be able to remove the bottom tray of beautiful vermicompost and have very few worms, if any, still down there. I’ve had my worms about three months and am on my second tray. By the time gardening season arrives next Spring I should have a good supply of the world’s best fertilizer, totally organic and, other than my startup costs, absolutely free. I love my worms. I talk about them all the time. My friends are waiting for me to name them, at which point they will start to worry. Don’t tell anyone, but Wiggly is my favorite!