Put worms to work: Humble creatures’ manure helps Modesto-area gardens grow
Experts are spreading the word about a homemade source of garden fertilizer: Worm poop.
The Master Gardeners of Stanislaus County held a class on making vermicompost, as the stuff is called. It happens in bins roughly 18 inches deep, where purchased worms consume fruit and vegetable scraps and other items.
A few months later, the bins yield compost ready to be applied in the garden. It’s also known as worm castings.
“It’s a great fertilizer,” said Dennis Lee, one of the instructors. “It’s very inexpensive for you to produce. You can do it indoors. There’s very little odor – actually, no odor.”
The Master Gardeners are part of the University of California Cooperative Extension. The volunteer instructors get intensive training on irrigation, pests, soil and related topics. They pass on the knowledge to the public via phone and social media, at nurseries and special events, and at the extension office at the Stanislaus County Agricultural Center.
It was at the center that the Nov. 14 class on worm composting took place. Lee explained the process along with fellow Master Gardeners Ted Hawkins, Terre Gouveia, Rhonda Eriksen and Royce Rhoads.
The term “vermicompost” derives from “vermis,” the Latin word for worm. The basics:
Buy some worms: Red wrigglers are the preferred type, available from specialty farms. The nearest is PJ Dunn Working Red Worms in Galt, according to an online listing by CalRecycle, a state agency devoted to reducing waste. A vermicomposter typically starts with about 1,000 worms. Common earthworms also enrich the soil, but they are not advised for composting because they do not like being disturbed.
Get a bin: Gardeners can purchase ready-made plastic bins from worm suppliers or make their own from wood and other materials. The bins should have holes to allow aeration and drainage. Keep them in spots that don’t get too hot or cold.
Add the bedding and worms: Fill the bin with moistened bedding, which can be shredded paper, dry leaves, sawdust and other high-carbon materials. Avoid glossy paper. Add the worms, which will then start consuming the bedding.
Add food: Various foods should go into the bins in the ensuing weeks, such as fruit and vegetable scraps, grains, coffee grounds and grass clippings. Avoid meat and dairy. If the bin gets smelly, it could mean it has too much food in it.
Harvest castings: They are ready in 2 1/2 to six months, depending on the number of worms and the amount of food they have turned into manure. An easy harvest method involves placing new food in part of the bin, which will draw the worms off so the castings can be collected. The worms then can start working on the next batch of compost.
The UC system launched the Master Gardener program in 1981, but it did not reach Stanislaus County until last year. The local unit has enough people for the training that starts in January 2020. Another will follow in 2021.
Worm castings are not a major commercial product in and near Stanislaus County, but they might sometime have a bigger role. The Fanelli Dairy, west of Hilmar, installed a trial system using worms to break down nitrogen in manure-laden wastewater that irrigates feed crops.
The project got a grant from federal Natural Resources Conservation Service. It also had support from a group called Sustainable Conservation, which works with farmers out of offices in San Francisco and Modesto.
This story was originally published December 2, 2019 at 1:47 PM.
