EARTHWORMS

At VermiCo, we’ve chosen to focus on one species, Eisenia fetida, (pronounced eye-SEN-ee-uh FE-ti-duh) a composting earthworm, for several reasons. First, it is a durable earthworm, well-suited for the rigors of harvesting and shipping. Second, it tolerates a wide range of temperatures—from nearly 90 degrees Fahrenheit to nearly freezing. (Other, more exotic species are less tolerant of temperature extremes). Third, Eisenia fetida earthworms (also called redworms or red wigglers) are extremely prolific, largely due to consistent production of cocoons with remarkable hatching rates of young that reach sexual maturity in as few as seven weeks. Some have claimed these earthworms, when conditions are optimal, can double their biomass (weight of live earthworms) in 60-90 days. And finally, redworms are the most commonly used species throughout the vermicomposting industry. For obvious reasons, an earthworm that is the most widely used and traded will have the greatest demand and value.

A conservative guestimate is that E. fetida earthworms process at least ½ their body weight per day in organic material. However, this amount depends on the presence of key process variables—temperature, moisture, porosity, and quality of feedstocks. These earthworms are capable of consuming their full body weight and even 1-1/2 times their weight when conditions are right. Their food consists primarily of microorganisms within decomposing organic matter where carbon sources (such as dried leaves, shredded paper, cardboard) have been mixed with nitrogen sources (such as vegetative food waste, grass clippings, manure). Earthworms thrive best in a warm, very moist, aerobic, dark, little-disturbed environment of 100% decomposing organic matter. Toxic elements such as salt and high ammonia concentrations can be lethal. Vermicomposting happens best when there is plenty of moisture in an aerobic environment at temperatures between 65-80 degrees.

Our earthworms are sold by weight, not by count, since no one spends time counting thousands of earthworms. While it has been estimated there are approximately 1,000 adult Eisenia fetida earthworms per pound, we simply state that we will ship live earthworms by the pound—not worm count or size. Larger sized worms tend to get harvested and shipped.

To innoculate a new system where bedding is present, we suggest a minimum of one pound of earthworms per square foot of area. Where more information is desired, we recommend book #103 Worms Eat My Garbage for a thorough treatment of small-scale, home and school vermicomposting and book #101 Commercial Vermiculture for details about growing earthworms for profit in larger-scale systems.

The goal of vermicomposting (composting with earthworms) is to convert our garbage into the earthworm’s gold….castings. Worm castings can be added to potted plants, gardens, lawns, trees, bushes, and made into potting soil (use only 20% by volume in mixes). Liquid extracts called castings teas can be made and sprayed on plants for foliar feeding and used as a bio-insecticide or used as a soil drench. Unfortunately our space here does not permit a full description of the many exciting discoveries now being made in earthworm science and soil ecology, particularly in the area of horticulture and agriculture where plant growth trials and bio-pest control tests have proven nearly miraculous benefits of using earthworm castings.

Orders of 100+ pounds or more: Call for prices