Sonoma farmer turns to worm composting

Jack Chambers held up a handful of rich, black compost.

It squirmed.

Hundreds of aptly named red wriggler worms were writhing within it.

"These worms are made for composting," he said proudly, giving their Latin name - Eisenia fetida. "This was pure cow manure just weeks ago - notice that there is no smell and no flies."

Chambers, a pilot for Delta Air Lines, has done double duty as a worm farmer for the past 18 years. He and his wife, Lois Chambers, own the Sonoma Valley Worm Farm ( www.sonomavalleyworms.com), which produces "vermicompost" (worm waste and other organic material) for vineyards and farms, and sells worms by mail order throughout the Bay Area.

The Sonoma farm's motto: "Join the underground movement."

Now the Chambers family is launching a new worm endeavor: a worm composting system for places producing large quantities of organic waste such as farms, horse stables, restaurants, wineries, universities and business campuses.

"Instead of paying money to have their waste hauled away, they can compost it and put it back on their property," said Amy Grimes, Lois' daughter, who is involved with the project as its marketing manager.

The family will introduce the patent-pending VermiComposter CF and Aerated Composting System in January at the U.S. Composting Council annual conference in San Jose.

It's a far cry from a home worm bin. At $20,000 or so, it can handle about 1 1/2 cubic yards of waste a week - the amount of manure produced by four to seven horses in a week.

Continuous flow

The system consists of three bins with a timed forced-air blower for an initial two-week aerated composting period to kill pathogens and weed seeds, and then either a 20-foot or 40-foot "continuous flow" bed where 150,000 or 300,000 worms can get to work munching, digesting and excreting the material. The continuous-flow feature means compost can be harvested weekly; the 20-footer produces half a cubic yard a week; the 40-footer, a cubic yard.

Grimes, 34, went back to school in part to help with the new worm project and also because she was disheartened by the waste she saw working as an event planner. This month she received a Green MBA from Dominican University in San Rafael and focused on a business plan for the worm farm as her capstone project.

She said her research showed an opening in the market for a mid-range system; most other worm composters are either bins for single-family use or mega enterprises that handle municipal waste.