This month I thought I’d explore a topic that's new to me. This activity isn't usually done inside greenhouses, but I do think it's of interest to gardeners. What is an efficient, odorless way to recycle food wastes, producing compost at the same time? The answer is vermicomposting, or the farming of worms.
An average family generates nearly four pounds of food waste a week. In addition to using this untapped resource in our kitchens, worms consume shredded paper—another material most of us can certainly provide! And the resultant worm castings, rich in nutrients and trace elements, are a valuable addition to garden soils.
The basic process is straightforward. Dry material, including shredded newspaper and dry leaves is topped with a handful of sand. The worms are placed on top and then a layer of fresh kitchen scraps is added—then water. The entire arrangement is made inside a container—often made of plastic– provided with air holes. The worms naturally crawl up towards the continuing source of food, and as scraps are added, their castings accumulate below. As long their needs are met, they flourish and reproduce. It's best to keep your worms out of hot sun and heavy rain. Temperatures should not dip below 40 degrees F. When ants are a problem, place shallow containers of water at the base of the container.
Epigeic worms are surface-dwelling worms, which are not the same as the(endogeic) worms that we find when we dig in our gardens. Unlike those sub-surface inhabitants, which promote soil health by creating tunnels that encourage aeration and water retention, these worms eat matter that falls on the surface of the soil; they have especially high metabolisms and live in dense colonies. Specialists in waste management, they process as much as their own weight each day. Because they are acclimated to an ever-changing and relatively dangerous environment, they tolerate the stress of being handled and harvested well. So, don't just go out to the garden and dig up worms for your composting project – those are not the same worms.
Worms Eat My Garbage by Mary Appelhof, is the original and definitive guide on keeping red worms. I found the website www.redwormcomposting.com to be a comprehensive and quirky one on the topic; check out http://www.7dvt.com/2008/wiggle-room too.
One of the most exciting applications of vermicomposting is its adoption in classrooms as an educational tool. Numerous packages that include worms and containers for growing them in classroom settings are available online. On some scale, farming worms might make sense for you too.