Put Worms to Work for Your Garden
(and help save the planet too!)
by Scott Vlaun

Aristotle called them the "intestines of the earth." According to Darwin, who spent 39 years studying worms, "It may be doubted whether there are many other animals which have played so important a part in the history of the world, as have these lowly organized creatures." While some might disagree, it is certain that these fascinating animals have an important role to play in the organic garden, and may also help us towards a sustainable future for the planet.

For many of us, our introduction to worms came as we collected them for fishing bait on the wet grass in the early morning hours. As organic gardeners our relationship with these soil dwelling creatures continues as they appear (hopefully) whenever we work the soil, quickly burrowing to get out of the light. Another increasingly common worm experience these days is vermicomposting, or using worms to digest waste organic material in controlled situations, creating a rich organic fertilizer in the process. Both encouraging worms in the garden, as well as using them to compost wastes can be excellent ways to increase the vitality of your garden, but are distinctly different processes involving distinctly different types of worms.

The common earthworm, or night-crawler, that is found in rich garden soils is most likely to be Lumbricus terrestris, while the red wiggler worms used in vermicomposting are generally Eisena fetida. A close relative, Eisena andrei, is also used for this purpose as are a few other species. Commercial red worms purchased for composting may contain both E. fetida and E. andrei. Earthworms are as poorly suited for vermicomposting as red wigglers are for life in the garden (at least in northern climates), so it's important to have the right worms for the job.

Worms In The Garden

There may be no harder worker in the garden ecosystem than the earthworm. Earthworms are voracious consumers of organic materials and leave a nutrient rich manure called castings in there wake as they work their way through the soil, cycling nutrients between the soil surface and as deep as six feet below. As the castings are neutral in pH, healthy earthworm populations can help to mitigate problems with either high or low pH. In addition to producing up to half of their body weight in nutrient rich castings every day, earthworms also improve garden soils by creating channels which help to aerate the soil and improve drainage, while their slimy, nitrogen-rich secretions help to bind soil particles and increase moisture retention. A soil that is host to a burgeoning earthworm population is likely to be nutrient rich, highly friable, and a joy in which to garden.

Even though the earthworm is actually an 18th century European immigrant to North America, it has since become fairly ubiquitous across the continent. Rich organic soils are reported to harbor up to a million earthworms per acre. So if you want a healthy earthworm population in the garden, it's generally not so much an issue of "importing" worms as it is providing optimal conditions for them to prosper. Avoiding practices that damage or discourage worms, such as applying chemicals, excessive rototilling or spading, as opposed to using a digging fork which leaves the worms unharmed, can also help increase populations.

For earthworms to thrive, they need an ample supply of organic matter, adequate moisture, and oxygen. Additions of compost or well-rotted manure to the soil and thick mulches of shredded leaves, grass clippings, and other organic materials will encourage worm activity by providing food and habitat. In soils that have been severely depleted or heavily treated with chemical fertilizers and pesticides it may take many years to build healthy populations. If good conditions are present for worms and none at all are spotted for a year or two, it might help to bring in a can full of worms from a neighbor's garden for "breeding stock." One of the best gifts my wife and I received when we got married was a can of fat earthworms that we tucked under a pile of mulch in our new garden. The population has continued to grow ever since, and after five years, we rarely turn over a fork full of soil without seeing a worm or three.

Worms To Save The World And Enrich The Garden

A large part of the organic waste generated worldwide ends up choking landfills, producing harmful greenhouse gases as it rots, and creates serious disposal problems for local communities. From kitchen waste to livestock manure, there's just no "over there" to put the stuff any more. Enter the red wiggler worm. From small bins in pantries and cellars, to large-scale commercial vermin-composting operations, billions of red wigglers are literally eating our garbage. On the output end of the system, the use of nutrient-rich, worm casting based products, instead of mined chemical fertilizers, further helps to protect the earth, air, and water from toxic pollution.

Unlike Earthworms that burrow deep into the soil, red wigglers work just below the surface of the soil "litter" converting organic materials into a rich fertilizer. These amazing creatures can eat up to half of their body weight every day and can double their populations in as little as three months. They can eat everything from vegetable scraps and shredded newspaper, to coffee grounds and filters, teabags, and aged manure, but generally not meat and dairy products, although some vermicomposters report success with them in small amounts. The worms can survive at temperatures from around 50–90°F (10–30°C) but near 70°F (20°C) is optimal, so in northern climates year-round vermiculture is an indoor activity. A well maintained worm bin has little or no odor though, so that shouldn't be a problem. The important thing for a pest and odor free bin is to feed the worms only what they can eat and to keep the surface covered with wet burlap or other material.

With the rise in popularity of vermiculture, the internet has many valuable sources for information, (see below for a listing of websites) and books are available from bookstores and libraries. Seeds of Change sells a ready made worm farm or if you have time you can build your own. We also sell red wiggler worms and The Worm Book by Loren Nancarrow and Janet Hogan Taylor which has detailed explanations of how to start your worm composting operation. Seeds of Change also is proud to offer Laughing Crow Worm Compost this year. We have found it to be an excellent soil amendment both in the garden and for container gardening and by supporting their operation we are helping to keep tons of waste out of landfills.

Whether in the soil or in the worm bin, put worms to work for your garden this year. You'll reap the rewards of healthier plants and a healthier planet.

Scott Vlaun
Editor

Websites and Resources

University of Nebraska
http://lancaster.unl.edu/pest/resources/vermicompost107.shtml

Master composter.com
http://www.mastercomposter.com/worm/wormcomp.html

The "Burrow"
http://www.jetcompost.com/burrow/index.html

Cornell Composting
http://compost.css.cornell.edu/worms/basics.html

Photo captions: (1) A worm in the palm is worth... (2) Another handful of worms (3) A worm farm available from Seeds of Change