A Detailed Guide to Earthworm Artificial Rearing Methods and Techniques

There are many methods for artificially rearing earthworms, and the rearing method should be determined according to the rearing purpose and rearing conditions. Below are some methods suitable for small- and medium-scale earthworm rearing.

I. Pot Rearing Method

Flower pots, plastic pots and other waste ceramic vessels are used for rearing. This method is suitable for small-scale rearing for indoor experimental research, because it is simple to rear, easy to manage, convenient to operate, the rearing conditions are easy to control, and the experimental data are also easy to measure. However, because the pot volume is small, many worms cannot be reared, so it is difficult to apply in production.

When rearing earthworms in pots, the feed loaded should be 3/4 of the pot height, and about 100-200 earthworms per pot is appropriate. Because the pot body is small, the humidity and temperature inside the pot change greatly due to environmental influence, for example, the feed tends to dry out and the temperature varies markedly. Therefore, on the premise of ensuring ventilation, the pot mouth can be covered with plastic film, and water should be sprayed frequently to maintain suitable humidity of the feed in the pot. Or, as the outside temperature rises and falls, the position of the pots should be moved frequently to regulate the temperature inside the pots. In addition, the rearing time in pots should not be too long, and 30-60 days is mostly appropriate.

II. Box and Basket Rearing Method

This is one of the most commonly used rearing methods. The box and basket can be made of wood, bamboo, vitex twigs, rattan, plastic, and so on. The specifications of the rearing box length, width and height include the following: 60 cm × 30 cm × 20 cm, 60 cm × 40 cm × 20 cm, 60 cm × 50 cm × 20 cm, 60 cm × 20 cm × 30 cm, 60 cm × 40 cm × 30 cm. The bottom and sides of each box or basket must have small drainage and ventilation holes, with a diameter of 0.7-1.2 cm being best, so that it can both ventilate and drain water while the earthworms will not crawl away. The total area of the small holes in the whole box can account for 20%-30% of the box bottom or box side area. Both sides must also have symmetrical handle grips for convenient hand carrying and operation. The feed in the box is piled to a height of about 16 cm; too much feed easily causes poor ventilation in the box, while too little feed dries out easily and affects the growth and reproduction of the earthworms. The amount of earthworms put into each box is about 5000-10000. When the rearing scale is relatively large, the boxes can be stacked up to become three-dimensional box-type rearing, but they should not be stacked too high, and generally 4-5 layers is appropriate.

This rearing method occupies little land, uses little manpower, is also convenient to manage, and has relatively high production efficiency. However, wooden and bamboo boxes and baskets rot easily when wet, so where conditions permit it is best to make them from plastic, which is not only durable but also uniform in specification, and is also conducive to improving the rearing effect.

III. Pond Rearing Method

This method is mostly used for rearing earthworms in China, and building ponds to rear earthworms is suitable for indoor and outdoor rearing. The rearing pond is built with red bricks into a pond 50 cm long, 50 cm wide and 15 cm high. The inner and outer walls of the pond are not coated with cement or lime, so as to maintain ventilation. The pond bottom can be a cement floor or a mud floor, but it must be tamped solid and leveled. A small opening is left at the bottom of each of the four corners of the pond to seep out excess water, and the opening must be covered with plastic mesh or wire mesh to prevent the earthworms from escaping or other harmful animals from entering and damaging the earthworms. If the amount of earthworms put in is not large, the pond can be divided into several small ponds, which not only facilitates rearing management but can also increase the yield per unit area.

For indoor pond rearing, old pig houses and chicken houses can be chosen. The interior must be kept dark and damp; the light should not be too strong, but ventilation must be good so as not to affect the growth and reproduction of the earthworms.

IV. Soil Trench Rearing Method

In or around fish, soft-shelled turtle and frog farms, choose a shady, damp place with good drainage, dig a trench 60 cm wide, 40 cm deep and 1 m long, and build an earth ridge 20 cm above the ground around it to prevent surface water from flowing in. Then, after tamping the trench bottom and the surrounding trench walls solid, put in feed 30 cm high, then put in 3000-5000 earthworms, and finally spread a layer of weeds on top of the feed and cover with plastic film to protect against sun and rain. After putting in the earthworms, water must be sprayed regularly to keep them moist, the feed in the trench must be replenished promptly after it is eaten up, and the earthworms must be harvested regularly. This method requires little investment and gives great returns, and is suitable for supplying animal feed for poultry, fish, soft-shelled turtles and frogs.