Dumps of organic waste piled on barren lands is a regular sight around our city outskirts. According to a CIPS-ASCI study on waste management, the top eight cities in India generate an average of 4,500 tons of solid waste every day or 36,500 tons in total. This figure excludes the uncollected waste and sewage water that flows down our rivers! These create environmental hazards. However, recycling processes can filter these waste materials into usable items benefiting our environment and society.
Vermicomposting is the most eco-friendly recycling process to reduce organic waste. This recycling process not only converts organic debris into high quality compost but the chemical changes that the debris undergoes makes the nutrients easily available to the plants. Vermicomposting also can reduce heavy metals and toxins found in sewage slush. It has also been found that vermicomposting helps to significantly reduce the presence of pathogens in organic matter.
What is Vermicomposting?
Vermicomposting is a recycling process, where earthworms are allowed to eat organic waste to convert it into manure rich with exceptionally high nutritional content. Vermicomposting is practiced through ‘Vermiculture’ literally meaning ‘to grow worms’ or ‘worm farming’. Earthworms (Lumbricus rubellus) are cultivated in agricultural farms to consume organic waste including all kinds of biodegradable wastes. They then give out the excreta, which is known as ‘vermi-cast’. These vermi-castings are rich in nitrate and contain minerals like phosphorous, potassium, calcium, and magnesium, which are excellent fertilizers and soil conditioners.
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The Process of Vermicomposting
The vermicomposting process can be carried out not only in large-scale agricultural farms, but also at our own homes to make organic manure for our kitchen garden.
The basic requirements for composting to start are:
- All the organic waste that one can collect – dry leaves, fruit peels, rotten vegetables, stale food, etc.
- A deep container made up of either wood or plastic to store waste materials
- Red wiggler earthworms, which are widely used since they voraciously eat up all types of organic matter
- Any biodegradable material that is high on carbon content to serve as bedding for the earthworms to live on as well as to keep the worm container moist. Shredded cardboard paper, office paper, any paper towel, newspaper and coir fibers are often used as bedding. Before putting the bedding into the container, it needs to be hydrated with water for at least a day such that it retains the moisture. However, the excess water has to be squeezed out before it is put inside the container.
Vermicomposting is a slow process, which can be done in two ways:
- Bed Method: Beds of organic matter are prepared. This is an easy practice and is widely used.
- Pit Method: Cemented pits are made and are filled with organic matter. However, this method is not preferred as we have problems like water logging and poor aeration.
As earthworms feed on waste, they begin to excrete a dark colored, nutrient-rich organic matter called ‘vermi-cast’. For a successful production of good compost, the castings need to be removed frequently, so that the worms can continue to harvest the remaining waste material. There are two ways to do this:
- Put light into the container. When the worms face light they go deep inside the bedding at the base. The vermi-cast can then be removed
- Push aside all the castings on one side and put fresh waste on other side of the bin. After a week or so, the worms start working on the fresh garbage to produce new compost
When the worm container gets filled with the compost, it can be used as manure for gardening or for farming purposes.
Vermicomposting at home
Image – Flickr/Paul Stockamore
The process of vermicomposting at home is fairly simple. It involves:
- Mixing cow dung with organic kitchen material at a ratio of 3:1 and keep aside for decomposing for about two weeks at a warm temperature of 30 degrees
- Beds of dimensions 6x2x2 feet are created the bottom of which is filled dried leaves in order to stop the migration of the worms into the soil
- These beds are filled with the semi-decomposed organic material along with the mixture of cow dung and kitchen left over
- Earthworms are released in the upper layer of these beds
- The beds are sprinkled with water for moisture and are tilled every 30 days in order to provide good aeration
- A by-product is obtained 45 days that is black and granular in appearance. This by-product is three-fourth of the total raw material that was used.
Precautions while Vermicomposting
- The compost pit should be protected from direct sunlight and a certain temperature has to be maintained
- Water should be regularly sprayed on the pit in order to maintain the moisture level
- The worms should be protected from natural predators
Examples of Vermicomposting in Indian Farms
A number of places in India have already implemented vermicomposting and have shown spectacular results:
Adarsha Watershed, Kothapally
Lakshmamma and four other women have set up a vermicomposting enterprise in a common place under a single roof. Having begun with a population of 2,000 worms of three epigeic species they regularly harvest around 400kg of vermicompost every month collectively. They have gained customers overtime and they earn money on a monthly basis.
Andhra Pradesh Rural Livelihood Project (APRLP)
Villagers living in Sripuram, a village in Mahbubnagar in Andhra Pradesh got introduced to vermicomposting as a part of APRLP. They learnt how to increase the per hectare yield of the crop with the help of vermicomposting in their farms.
Two farmers of Bundi nucleus watershed in Rajasthan have built a multiple compartment system of vermicomposting while many are following the regular vermicomposting. In Guna nucleus watershed in Madhya Pradesh, nearly 35 farmers from all the three micro watersheds are practicing vermicomposting.
Maharashtra Agricultural Bioteks
Maharashtra Agricultural Bioteks promotes the use of organic fertilizers in place of the chemical ones. The organization has been able to convince over 2,000 farmers to switch to vermiculture, who produce over 5,000 tons of vermicompost annually. The organization has also been successful in creating a vermicompost unit in Madhya Pradesh, which produces 5tons of vermicompost per month. Maharashtra Agricultural Bioteks has promoted this eco-friendly technique in 13 Indian states and also distribute vermicompost kits to housewives so that they can practice it at their homes.
Advantages of Vermicomposting
- It is a natural fertilizer
- It is not hazardous for the soil
- It improves soil aeration and texture
- Water retention ability is improved
- It improves the nutrient status of the soil
- This method is cost effective
Disadvantages of Vermicomposting
- Composting takes a lot of time to process (3 months)
- It produces bad smell
- There is a need spend time on maintenance as constant monitoring is required
- This technique requires a lot of laborers and is pretty hard to implement in urban areas