You Can Start Producing Earthworms in a Washtub

By Ronald Abe, William Braman and Ocleris Simpson.

Earthworm farming has become popular in recent years due primarily to demand for the worms as fish bait and to supply brood stock to the ever increasing numbers of new growers. Worms also are sought by organic gardeners for natural tillage of the soil.

Since earthworms are great consumers of decaying organic matter and micro-organisms, they may be used in future systems to decompose and recover nutrients from large quantities of organic wastes such as manure, garbage, and pulpwood sludge.

There also is the possibility of processing large quantities of earthworms into products to be used as a protein supplement for aquatic and farm animal production. The live worm contains 10% protein and if made into a dried product, 60% protein.

Cultural practices recommended in this chapter are for the small English worm which is also called "red worm", "red wiggler", or "red hybrid". It is the most popular farmed worm because of its hardiness and tolerance of high concentrations of decaying organic matter.

With some experience, many modifications in the cultural practices may be made for economic reasons without sacrificing yield. For cultivation of varieties native to your own area, observe the environmental conditions under which large numbers of worms are found and duplicate those conditions.

If ideal growth conditions can be sustained at all times, worms may be raised in mounds or windrows of organic soils without the use of a container or enclosing structure. Since we are humans and subject to making errors in growing earthworms, it is recommended that a container be used to prevent a massive escape of the worms during unfavorable conditions.

Use any container that is at least 10 inches deep and free of toxic chemicals. Make drain holes of 1/2 to 1 inch in diameter at the bottom. Smaller holes may become plugged with use over an extended period of time.

A three-inch layer of coarse gravel in the bottom will assure good drainage and prevent loss of soil from the container. A layer of sand may be placed on the gravel to fill the large spaces between the gravel and further improve drainage.

A galvanized washtub 2 feet in diameter and 10 inches deep, as an example of a container for a beginner, could be used to produce 4,000 to 6,000 mature size worms a year.

Building a Bed

Construct rectangular beds for large volume production of worms. Limit width of the bed to about 4 feet for easy access to the center during harvesting. Sides of the bed may be made of lumber, concrete block, brick or concrete slab.

Provide adequate drainage. To protect against flooding in areas of high rainfall or in culturing practices using liquefied feeds, use a perforated septic tank drainage line in conjunction with layers of gravel and sand.

Have walkways between beds for ready access to all areas of the beds.

Shade will help control moisture content of the bed during the hot summer months. A shed or building is the ideal location for the beds; however, the added cost may not justify the assurance against losses from heavy rains in certain areas.

A time-controlled automatic sprinkling system can be used to provide moisture and cooling in summer in the absence of shade. Water frequently and in small amounts.

In filling the bed use soil with a high content of decayed organic matter. Mix about two-thirds top soil and one-third decayed organic matter such as leaf compost, manure, sawdust, ground peanut hulls, peat moss, and other plant byproducts available in your area.

Test the mixture in a small container such as a flower pot or a clean gallon can with at least 25 worms. Make drain holes on the bottom, add a layer of gravel, and fill the container three-fourths full with the soil mixture.

Saturate the soil with water and let excess water drain, then place the worms on the surface. A 24-hour test will give you an idea about the porosity, drainage and other environmental conditions needed by the worms.

If the worms crawl out of the container, move to the gravel layer, or die from shrinking or swelling, try another mixture or seek help from your county Extension agent.

Fill the worm bed with a 6-inch layer of tested soil. Thoroughly water the bed with a spray nozzle or sprinkler, but not to the point of being soggy.