Vermicompost: How to Attract Worms to Your Garden

Use the free services of resident earthworms to make vermicompost, one of nature’s most potent fertilizers.

article image
by Dwight Kuhn
Cross-section of an earthworm burrow, with castings at the burrow entrance.

Learn how to attract worms to your garden for DIY vermicompost. Includes steps for a DIY worm bin to keep worms through the winter to make spring fertilizer.

Vermicompost, or compost made mostly by earthworms, is seven times richer in plant nutrients compared to compost created mostly by fungi and bacteria, and recent studies suggest that small amounts mixed into soil suppress diseases, slugs and insects. Numerous studies have shown that when only 10 percent of the volume of potting soil used to grow seedlings is vermicompost, a huge range of plants simply grow better — from carrots to tomatoes to zinnias. It’s easy to entice earthworms to work their magic right in your garden, or you can make vermicompost in enclosed bins, or both! In addition to improving soil fertility chemically with their castings (a mixture of manure and slime emitted through the worms’ skin), earthworms improve soil physically by opening airways and drainage holes as they travel.

Notice that I did not tell you to buy worms. That’s because we’re recommending “catch-and-release” worm composting, which involves learning how to attract worms to your garden and makes use of the earthworms present in your own yard. These species have already demonstrated their satisfaction with your unique climate and soil, though few (or none) of them are likely to be red wrigglers (Eisenia fetida), the species used in commercial vermicomposting systems. That’s ok. Common red worms (Lumbricus rubellus) and other species plucked from compost bins or soil (or rescued after flooding rains) usually make well-behaved captives, and you can usually coax larger night crawlers (L. terrestris) to colonize any spot by piling on plenty of mulch.

Indeed, when it comes to using earthworms to build soil fertility, Clive Edwards, Ohio State University entomologist and author of Earthworm Ecology — the academic bible on earthworms — thinks night crawlers deserve top priority. “The best thing is to obtain some L. terrestris and inoculate your garden with them. They are the most important species in promoting soil fertility,” he says.

  • Updated on Jun 22, 2023
  • Originally Published on Apr 28, 2008
Tagged with: Barbara Pleasant, compost, earth worms, night crawlers, vermicompost, vermicomposting
Comments (0) Join others in the discussion!
    Online Store Logo
    Need Help? Call 1-800-234-3368