Vermiculture means artificial rearing or cultivation of earthworms. The objective is to continually increase the number of worms in order to obtain a sustainable harvest. The worms are either used to expand a vermicomposting operation or sold to customers who use them for the same or other purposes.
 Benefits of Vermiculture
Vermiculture or rearing of worms is important for several reasons.
- Worms can be used for converting waste into organic matter and also fertilizers with high humus content.
- Worms have a number of other possible uses on farms, including value as a high-quality animal feed.
- Vermiculture offers potential to organic farmers as sources of supplemental income.
- The worms can also produce excellent organic pesticide.
 Types of Worms
There are several types of worms. These are:
- Anecic (Greek for “out of the earth”) worms are burrowing worms that come to the surface at night to drag food down into their permanent burrows deep within the mineral layers of the soil.
- Endogeic (Greek for “within the earth”) worms are also burrowing worms but their burrows are typically shallow and they feed on the organic matter already in the soil, so they come to the surface only rarely.
- Epigeic (Greek for “upon the earth”) worms live in the surface litter and feed on decaying organic matter. They do not have permanent burrows. These “decomposers” are the type of worm used in vermiculture and composting.
Compost worms need five basic things. These are:
- A hospitable living environment, called “bedding”
- A food source
- Adequate moisture (greater than 50% water content by weight)
- Adequate aeration and
- Protection from temperature extremes.
 Multiplication of worms
To enable the worms to multipy, several thnigs need to be ensured.
- Worms get adequate food (must be continuous supply of nutritious food)
- They have well aerated bedding with moisture content between 70 and 90%
- The temperatures are maintained between 15 and 30 deg Centigrade
- The initial stocking densities should begreater than 2.5 kg/m2 (0.5 lb/ft2) but not more than 5 kg/m2 (1.0 lb/ft2).
To preparea vermiculture pit, cow dung and dried leaves should be mixed in 1:1 proportion. Earthworm should be released into this pit @ 50 numbers/10 kg. The composting area should be kept dark by covering the mixture with a sack or husk. Sprinkle water over it time to time to maintain moisture level. This process can expect Compost worm populations to double every 60 days.
There are several precautions that need to be taken.
- Vermiculture pits should be protected from direct sun light.
- To maintain moisture level, spray water on the pit as a when required.
- Protect the worms from ant, rat and bird and
- Avoid putting meat and sea food waste in the feed as it attracts scavengers.
A balance between "green matter" such as kitchen waste and "brown matter" such as leaves is essential for the worms to feed and multiply. This is called "carbon to nitrogen ratio", and should be approximately 2:1 (C:N). This also helps in reducing odour. Initially, the worms should be fed a maximum of one-half their body weight in kitchen scraps in a day. After they have taken to the environment and the food, the feed can be increased to their entire body weight.
There are two methods of adding matter to the bin.
- Top feeding — organic matter is placed directly on top of the existing layer of bedding in a bin and then covered with another layer of bedding. This is repeated every time the bin is fed.
- Pocket feeding — a top layer of bedding is maintained and food is buried beneath. The location of the food is changed each time and often the bin is fed in more than one location. As bedding runs low more is added.
 Harvesting and Bin Design
Worm growers usually keep the density of the beds between 5 and 10 kg/m2. This ensures a high reproductive rate.
- Manual Harvesting: Manual harvesting involves hand-sorting, or picking the worms directly from the compost by hand. Taking advantage of the fact that worms avoid light, can facilitate this process. If material containing worms is dumped in a pile on a flat surface with lights on, the worms will quickly dive below the surface. The top layer of compost, which is free from worms, is removed. This process is repeated several times until there is nothing left on the table except a huddled mass of worms under a thin covering of compost. These worms can then be quickly scooped into a container, weighed, and prepared for delivery.
- Migration Harvesting (Screen): The screen method is very common and easy to use. A box is constructed with a screen bottom. The mesh is usually 1⁄4”, although 1/8” can be used as well. The downward-migration system is similar to the manual system, in that the worms are forced downward by strong light. The difference with the screen system is that the worms go down through the screen into a prepared, pre-weighed container of moist peat moss.
- Mechanical Harvesting: Mechanical machines are used to separate the worms from the compost. Large commercial farms use these. The worms are put in a long rotating tunnel and the worms are separated from the compost using the rotation movement of the tunnel.
References: OACC Manual of On-Farm Vermicomposting and Vermiculture Bogdanov, Peter - Commercial Vermiculture: How to Build a Thriving Business in Red worms Bogdanov, Peter - Casting Call Bogdanov, Peter - Worm Digest
 Useful Websites:
- A Venture Into Vermiculture
- "Linking organic knowledge"
- Recycled Organics Unit
- Alternative Organic
- Vermitechnology Unlimited
- Working Worms - DIY worm farming