Facts About Earthworm Soil

The Composting Association of Vermont promotes earthworms as free fertilizer factories for soil. They provide many benefits without requiring food or water and reproduce in place, eliminating the need to purchase or add individuals after the initial population is established.

Nutrient Benefits

• Worm castings consist of organic matter that is partially digested and therefore more available to plants. They also increase the nutrient content of soil. The School of Agriculture in Ebenrain-Sissach, Switzerland, compared soil samples that contained worm castings against samples of soil without them. Soil with worm castings had, on average, four and a half times the potassium and seven times the nitrogen.

Earthworm Movement and Soil

• Earthworm burrowing improves water and air circulation, and mixes organic and mineral substances in the soil, according to the the Regional Alliance for Information Networking. Earthworms have been found 26 feet below the surface of the Earth, and some speculate they are most likely present far beyond that depth.

Earthworm Care

• While earthworms do not need supplemental food and water, they do need moist soil and freedom from chemicals. Pesticides and other chemicals commonly used in farming kill earthworms, so growers must weigh the pros and cons of chemical fertilizers and pesticides against the importance of earthworms.