A group of 30 enterprising farmers from Bantry, West Cork, formed the Celtic Worm Company in an attempt to harness the converting power of earthworms and provide local employment and income.

Slurry and farmyard manure supplied by local farmers is broken down into earthworm casts by millions of earthworms held in special vats on a farm close to Bantry town. The worm casts fall to the bottom of the vats and are collected at regular intervals. These casts are transported to an industrial unit on the outskirts of the town.

Here, the casts are packaged and sold as Celtic Gold Compost for plants to local garden centres. The company currently has five full time employees and employs another 12 people at peak production.

Indeed, earthworms are heroes of the soil for their effect on soil fertility and drainage, according to Teagasc.

Plenty of earthworms indicate a fertile, healthy, free draining soil, as earthworms till, separate and fertilise the soil, breaking down organic manures into plant available forms, improving the soil structure as well as the nutrient and water holding qualities of soil.

Earthworms eat organic manures and waste such as slurry and farmyard manure providing healthy soil and organic fertiliser in return.

As worms move through soil and decaying organic matter they ingest and aerate depositing castings as they go. These castings are rich in nutrients and beneficial soil organisms.

A worm’s gut contains enzymes and masses of bacteria and microbes and everything that passes through the gut of an earthworm is coated with these beneficial microbes and bacteria. It’s these microbes which play a major role in determining soil fertility. The worm cast restores microbial richness and diversity to soil that has been exposed to chemicals in sprays and chemical fertilisers.

Soil structure is hugely influenced by earthworm aeration and drainage channels. Compacted soils will show a distinct lack of earthworms which in turn will lead to increased drainage problems. Soil compaction caused by livestock and machinery, along with prolonged wet weather conditions, will make soils difficult for earthworms to work and collapse existing channels formed by earthworms.

Earthworms contribute to more effective breakdown of applied organic manures (slurry, FYM) and increase aeration, drainage and contribute to increased soil health.

Other Earthworm Uses
Researchers have identified and named thousands of distinct species of earthworm, but only a few have been identified as useful in what is known as ermiculture systems. Luckily these obliging earthworms can tolerate a wide range of environmental conditions, unaffected by handling or the disruption of their habitat.

By Anthony O’Connor, Teagasc Adviser, Galway/Clare Regional Unit