Worm Composting Becomes Big Business

A few weeks ago we caught a behind-the-scenes glimpse at an industrial composting operation. But it's not just regular composting that's going mainstream. Vermicomposting, or worm composting—which I tend to think of as the crunchier, DIY end of composting—is also being practiced on some pretty large scales. And these folks seem to be making money from it too.

Janice Sitton has an excellent article over at NC State University's website (originally published in BioCycle magazine), which documents the goings on at NC State University's 10th Annual Vermicomposting Conference. From a 40-acre facility in California selling 300 lbs/week of worms, and over 4,000 tons/year of castings, compost and soil amendments, to a Pennsylvania facility that treats 10 wet tons/week of biosolids from waste water treatment facilities, these are clearly no small-scale operations. Most seem to make their money from a variety of income streams—selling worm castings and extracts, but also selling worms themselves and other products.

Crucially, as Sitton explains, vermicomposting is not just another waste reduction methodology, or a way to make compost faster or more efficient—there seems to be a qualitative difference in the end product that results in better plant growth and decreased instances of disease:

"The typical loss rate in the early 2000s for grape vine plantings was 25 percent, but with a trial application rate of one cup of vermicompost per plant, only two of 400 plants were lost at the vineyard located on the Worm Farm. A famous Napa vineyard using vermicompost planted two acres of vines, and had no vine loss whatsoever."

These kinds of anecdotes from vermicomposters themselves appear to be backed up by academic research. In fact, tests by Norman Arancon of the University of Hawaii suggest that application of vermicompost showed significant and repeatable suppression of pythium, verticillium wilt, rhizoctonia solani, powdery mildew, plant parasitic nematodes, cabbage white caterpillars, cucumber beetles, tomato hornworms, mealy bugs, aphids and two-spotted spider mites' damage to a broad range of edible crops.

That worm poop is good, errm, stuff.