Worm Farming (Vermiculture)
Author: Mary Murphy - Full Cycle (Wormfarms)
( Article Type: Sustainable Development )
“Without earthworms there would be no plants on the planet” Thomas Pakenham, Interview, Nov 2008
Earthworms have an impact on nearly every aspect of our world. They ‘recycle’ and reduce the volume of waste, they increase water infiltration and retention, they bind carbon into the soil, they till and aerate the soil, they multiply nutrients and present them in plant soluble forms. They decrease disease and infestations; they remove harmful pathogens, and are used to remove heavy metals and radioactivity from damaged soil. Anglers use them as bait and in some countries they are used as a source of food. Charles Darwin’s study of earthworms spanned 39 years. It is reputed that he devoted the last few years of his life to the study of earthworms stating: “It may be doubted whether there are many other species in the world which have played so important a part in the history of the world than the earthworm.” (The formation of vegetable mould through the Action of Worms, Darwin, C. 1881) His study laid the foundation for many studies throughout the world. There are approximately 4,600 identified species of earthworms and an estimated 2,000 yet to be categorised. Their impact reaches from the soil through our landfills to the air we breathe.
Nature knows no waste!
In nature what ends one cycle is used to begin another. Nothing is discarded or goes unused. Humans consume resources and when finished discard what remains. We have developed complicated systems to manage what we discard. In the past we have managed our waste by building landfill sites where all our waste ends up. Until recently, our waste management system was based on the collection, cleansing and disposal of waste. With South Africa’s Waste Management Act, gazetted on 10 March 2009, we are now legally obliged to reduce our waste.
Ironically, organic waste is the most difficult type of waste to collect and dispose of and yet it has the greatest potential as a resource. It is estimated that 30% of waste produced in households is compostable. This percentage is estimated at 70-80% in hotels and restaurants.
When organic waste is disposed of on landfill sites it can take it 20-30 years to decompose, if at all. Earthworms take what we consider waste and within a few days convert it into liquid and solid fertilisers that can be used to improve soil and increase crop production. Worm farming has become a practical and cost effective way of dealing with organic waste and a wide variety of worm farm units are available to be purchased ( you get what you pay for in terms of product quality and the environmental and social aspects of the design ).
The digested organic waste that is passed through a worm farm is collected and used in the form of ‘vermicastings’ or ‘vermi-tea’. These are full of nutrients and trace elements and are fantastically good for gardens (especially crops and vegetables). Studies conclude that earthworm castings contain ten times more nitrogen, potassium, calcium, magnesium, and phosphorous than topsoil. The castings increase soil aggregates and improve the porosity of the soil, thereby increasing water infiltration and retention. Castings also act as an insect and disease repellent and control pathogenic bacteria. Whilst an increasing number of farmers around the world are using vermitea and vermicast to grow their crops (including wine estates, avocado, tomato, citrus, potato, strawberry and commercial flower growers – who all report better crop yields and crop quality) worm farming is becoming increasingly popular for domestic use amongst those who wish to take active steps to live in a more eco-friendly way
