The vermicomposting industry brings together earthworm growers, farmers and livestock operators on the supply end with a wide range of potential clients that include nursery and orchard owners, greenhouse growers, golf course managers, soil blenders, food service managers and solid waste managers. The overall goal is to take surplus organic matter and recruit the composting worm, Eisenia fetida, to convert the waste into black gold--vermicompost.
In the American South, Ontario and elsewhere, growers have for generations collected or raised worms as bait for anglers. In the mid-1970s, scammers attempted to recruit new vermicomposters with grandiose claims based on the actual ability of composting worms to double their population in two to four months. The scams involved pyramid-style buy-back schemes. A Securities and Exchange Commission investigation closed down the scams. By the late 1990s, the United States had several hundred large-scale worm wranglers involved in legitimate vermicomposting industries.
Some sites are using 100,000 to 500,000 lbs. of worms to convert waste into vermicompost, writes Niir Board in "The Complete Technology Book on Vermiculture and Vermicompost."
The vermicomposting industry accepts municipal waste, factory and mill sludge, farm wastes such as animal manures and sugar cane cuttings, and even toxic industrial waste. The composting worms eat the waste and secrete castings, or manure, rich in beneficial nutrients and microbial activity that can be used as a soil amendment. Saleable products in addition to vermicompost itself include worm tea (a liquid made from a castings infusion) and surplus worms for bait or home vermicomposting.
Large-scale vermicompost operations can be found worldwide, with India pre-eminent in seeking new applications. Board, a project consultant, suggests that vermicomposting could make a useful cottage industry in India's areas of poverty, if cooperative societies could employ youth to collect organic waste and sell the vermicompost back to the village. Operators in the Philippines, the Netherlands, the United States, Argentina and many other nations undertake large-scale outdoor worm composting systems. The Worm Research Centre in the north of England notes that there are at least several hundred large-scale vermicomposting operations in the United Kingdom.
Vermicomposting pioneer Mary Appelhof writes that "this neophyte industry is plagued by lack of industry-defined standards, product consistency, and product availability." Large-scale continuous flow systems may be able to eventually produce high volumes of a consistent, high-value product. Some state governments, such as that of Georgia, which boasts a mild climate conducive to year-round outdoor vermicmposting, offer support to growers in the fledgling industry.
Finding markets for niche vermicompost products takes long-term dedication, indicates Canadian researcher Glenn Munroe in the "Manual of On-Farm Vermicomposting and Vermiculture."