Commercial Vermiculture FAQ

Q. Why is commercial vermiculture growing?

A. Worms have been grown on a commercial scale for the bait market for many years. But it has been just within the last quarter of this century that a profound shift has taken place. The new emphasis on vermiculture (raising or breeding earthworms) is in response to solving two pressing problems: 1) The problem of organic waste disposal, and 2) The problem of soil fertility.

Composting worms, such as the species Eisenia fetida, are recognized as a powerful resource in waste reduction. Capable of consuming anywhere from one-half up to their full weight in decomposing organic material daily, these earthworms also reproduce at a high rate under favorable circumstances. When moisture, temperature, feedstock, pH, and worm population density are at optimal levels, redworms are capable of multiplying at exponential rates. [However, extreme caution is advised for those looking to calculate worm reproduction and to translate those numbers into dollars. An unfortunate part of the expanding worm industry is the tendency of some to hyperinflate economic expectations based upon exaggerated forecasts of both worm reproductivity and the marketplace.]

In short, the interest in vermiculture today has much to do with the following:

  1. Earthworms have been successfully used in waste management. In scientific terms, they are used in the stabilization of volatile organic compounds. By reducing the volume of organic matter, through minimizing odor generation, and by the very real possibility of reducing or even eliminating pathogen levels, earthworms have been utilized in the conversion of organic waste to a stabilized, beneficial end-product.
  2. Some species of earthworms are capable of rapid reproduction.
  3. Worm castings or vermicompost has been found to be a highly regarded aid to soil fertility.
  4. While interest in this area continues to grow, the overall exposure to this phenomenon is nowhere near what it may be someday. Thus, its relative obscurity provides an opportunity for some to enter what many consider to be a growth industry.

Q. What is the difference between vermiculture and vermicomposting?

A. Vermiculture operations emphasize breeding earthworms for re-sale. A vermiculture business supplying worms as bait may concentrate upon raising large worms (with the idea that a larger worm catches a larger fish). Historically, many of these operations also sold worms based upon worm count, i.e., a number of worms was counted and sold for a given price. For some reason, this idea continues to persist in the present, in spite of the fact that no one is actually going to count 1,000 worms to sell for $5, $15, or $25. In fact, if there are about 1,000 adult redworms in a pound, these worms will be weighed (not counted), but unfortunately many still sell by the count. Referring to numbers of worms is confusing. With the new emphasis upon vermicomposting, worm biomass, i.e., the weight of a quantity of earthworms, is used to determine the quantity of feedstock that can be processed.

Vermicomposting operations emphasize transforming organic waste into a marketable product, vermicompost, through the activity of composting worms. In the largest vermicomposting operations, tipping fees are collected from haulers who bring material to the site. This material might be yard debris (leaves, grass, brush, limbs) which may have to be shredded and pre-composted. Other materials may include biosolids (the solid residue from wastewater treatment plants), food waste (pre or post-consumer), manures from herbivorous animals, and other feedstocks. The biodegradable fraction of municipal solid waste (MSW) has even been used as a feedstock for worms. Since vermicomposting facilities focus upon processing organic waste into a marketable soil amendment, vermicompost is regularly harvested and sold. Due to frequent harvesting, juvenile worms and cocoons are lost and, although worm reproductivity is generally considered to be high, vermicomposting operations see a fairly “steady state” in their worm populations. Thus, vermicomposters tend to focus on the process, while vermiculturists tend to focus on production of earthworms for re-sale.

The trend will be for more vermicomposting sites to be established around the world. Some vermicomposting systems will handle institutional (food) waste produced by schools, hospitals, military bases, prisons, and any operation with a cafeteria. These vermicomposting operations can be set up with on-site, in-vessel systems. Municipal-scale vermicomposting will continue to grow as more of the 4,000 composting sites in the U.S. begin to discover the advantages of producing vermicompost (a far more valuable commodity than ordinary compost) and blend worm castings in with their compost to create a more marketable product.

With this in mind, the issue of worm availability is raised. Vermicomposting sites, to be established, will need tens of thousands of pounds of worms in order to process tons of incoming feedstocks. Even a successful facility, once it is fully operational, typically cannot produce extra worms to start other facilities. Composting worms must be brought in from vermiculture sites (“worm farms”) where worms are raised for stocking the larger, vermicomposting operations. Such “worm farms” might also re-stock vermicomposting operations that have lost worms, due to toxic feedstocks, or improper monitoring where a “worm kill” has resulted. Even seasoned veterans have lost worms in their projects, with the result that they need to obtain more.

Q. What is vermicompost?

A. The terms vermicompost and worm castings have been used interchangeably to identify the resulting worm-worked material produced by earthworms. While the term castings identifies the worm’s excreta, or worm manure as it has been called, the term vermicompost allows for the presence of material left undigested by earthworms in the harvested product. This material may include fibrous, woody material from feedstocks as well as earthworm cocoons and inert materials such as rocks, glass, metal, plastic, etc. Castings seems to be the term of choice among industry personnel throughout North America, while vermicompost seems to be the preferred designation within the scientific community. While vermicompost seems to be a term of greater precision, at least two arguments for calling worm-worked material castings have been advanced. First, in the case of feedstocks applied that are nearly entirely digestible to earthworms after complete decomposition has taken place, and where a fine granular product is produced and passed through a screen of one-eighth inch or less, the presence of undigested organic material or inerts may not appear to be visible. Such a fine product, proponents of this viewpoint state, has such a high concentration of worm casts that it should rightly be called castings. If the material contains a significantly high concentration of earthworm excreta, then castings is the best term. Second, in the state of California, an agricultural exemption exists in favor of vermiculture operations excluding them from composting regulations. As an agricultural activity, the practice of vermiculture results in production not only of earthworms but earthworm by-products, castings. In the sense that cows produce milk and bees produce honey, earthworms produce castings as a marketable product. To call the worm-worked material vermicompost would too closely associate the material with compost, a product produced for sale by state-regulated facilities. Another opinion to this controversy adds that the term worm castings is more descriptive and better understood in the marketplace than the term vermicompost which may contribute to the perception that the material somehow contains compost.

Q. What about “hybrid” worms and so-called “Superworms?”

A. Scientific classification of earthworm species always uses scientific nomenclature (names) such as Eisenia fetida (redworms) or Lumbricus terrestris (nightcrawlers). Earthworm scientists have identified hundreds of species in existence around the world. There are no instances of hybrid worms having been created. Typically, one finds that where the term “hybrid” is in use, or a regional or descriptive name is used such as “Southern California Golden Whopper,” the earthworm in question is being advertised as something unique. These descriptive, not scientific names, are used to create the false impression that you can only get these special worms through this one vendor. In truth, the vendor is marketing an earthworm that has already been identified as a distinct species and this worm is most likely available through many other vendors.

Q. What’s involved in raising worms?

A. Worms can be raised on the ground (these are not burrowing worms, they’re composting worms) or in beds made of lumber or concrete block (actually, any container that provides drainage). They can be fed manure, compost, kitchen waste (fruit, vegetable, pasta, coffee grinds with filters, tea bags) paper (cardboard, newspaper, kraft paper, paper towels, etc.) but not meat, dairy, or dog doo-doo.

Q. What about extreme weather conditions?

A. Optimum temperatures for worms are between 50 and 80 degrees. Their habitat (worm bedding) serves as a kind of regulator of temperature extremes. For example, when the air temperature is 100 degrees F. you’ll find that when you place your hand in some soil, the temperature is much cooler. Similarly, the bedding for worms is warmer in cold weather conditions. However, insulation and heating systems can be created. VermiCo offers blueprints for constructing these.

Q. How do people usually get started growing worms?

A. Information is crucial. Your knowledge of what is involved and how to perform certain simple, yet important tasks will determine how much money you can make. Start by reading the literature we offer. You can order one of our package offers, including worms, but tell us that you want the worms delivered later, that is, after you’ve had time to read the literature and watch the videos you ordered, to get set up for your worms. Then, when you’re ready, we can ship the worms to their new home.

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