Vermiculture

The earthwords are cultivated and/or reared to increase their population. This a scientific process called Vermiculture. Vermiculture increases earthworm population; vermicomposting uses them to produce vermicompost. These earthworms are used to decompose organic wastes into a nutrient-rich material (vermicompost) to improve soil fertility.

In the 1970s, Mary Appelhof popularised the idea of vermiculture and vermicompost, where she used the earthworm Eisenia fetida to convert kitchen waste to worm compost.

Species Used for Vermiculture

Earthworm species commonly used for vermiculture include

Eisenia andrei (temperate)
Eisenia fetida (temperate)
Lumbricus rubellus (temperate)
Pheretima perionyx (tropical)
Lampito mauritii (India) or Perionyx excavatus (tropical)
Eudrilus eugeniae (tropical)

Techniques of Vermiculture

Harvesting for vermiculture can be done through three major techniques

Manual Method

Used for small-scale businesses of selling earthworms.
Earthworms are harvested from the soil directly by hand and kept in an organic layer.
The organic layer is kept on a flat surface and exposed to sunlight; as a result, the light-sensitive earthworms burrow below the surface.
The upper organic layer is removed, and once the earthworms are seen, they are harvested.

Migration Method

Take advantage of the tendency of earthworms to migrate to a new location for food and due to disturbances.
Screens are used; the collection box filled with peat moss is constructed around the screen.
The downward migration: Using light, the earthworms are forced to move downwards in the organic material, through the screen mesh, and are collected in the box below. The process is repeated until sufficient worms are obtained.
The upward migration: The bottom of the box contains a worm bed, and the upper region contains food (coffee grounds and manure from fresh cattle) and peat moss. The earthworms move towards the food and are collected in the box.

Mechanical Method

A mechanical harvester is used to collect earthworms.
The harvester is an 11ft long and 4ft cylindrical trammel screen (rotary screen) that separate materials, and is powered by an electric motor.
The walls of the harvester are made of screening materials with different-sized meshes.
Castings and the worm beds are added.
When the rotation starts, the worms will move across the trammel device and enter the wheelbarrow.

Process of Vermiculture

High amounts of organic waste, including plant materials and cattle dung, are mixed in an equal ratio.
Around 40-50 earthworms are released into this medium, which is kept protected from various environmental factors.
Regular maintenance of temperature (15°C-20°C) and moisture level (80-90%).
Within 30 to 60 days, the earthworm populations can increase several-fold under ideal conditions.

Vermicompost

The earthworm population gained through vermiculture are very useful for producing vermicompost. The worms consume organic wastes, farmyard manure, and roughages to produce a compost rich in nutrients and growth-promoting factors. Vermicompost is a beneficial way to improve the soil quality and promote the growth of crops, without using chemical fertilisers.

Frequently Asked Questions (FAQs)

Q1. What is the difference between vermiculture and vermicomposting?

Vermiculture is the rearing and multiplication of earthworms, while vermicomposting is the use of those worms to decompose waste into nutrient-rich compost.

Q2. Which species of earthworms are most commonly used in vermicomposting?

Eisenia fetida, Eudrilus eugeniae, and Perionyx excavatus are widely used due to their high reproduction rate and efficiency in decomposing organic matter.

Q3. Why is vermicompost better than chemical fertilisers?

Vermicompost improves soil structure, enhances microbial activity, and provides balanced nutrients naturally, without harming soil fertility like chemical fertilisers often do.