Vermicasting also called vermicomposting, is the processing of organic wastes turn into organic fertilizers through earthworms. Vermicast nutrient content varies with earthworm feed type, but feeding waste to earthworms does cause nitrogen mineralization, followed by phosphorous and sulphur mineralization after egestion.
Vermicasting can be done on a small-scale by homeowners with household organic wastes, on a large-scale by farmers with manure or by the food industry using organic wastes such as fruit and vegetable cull materials. Through proper design, vermicasting is a method of waste handling that is clean, socially acceptable, with little to no odour, requires no energy input for aeration, reduces the mass of waste by 30%, produces a valuable vermicast byproduct and even generates worms as fishing bait.
The driving force toward zero waste management is a global perception of the need to recycle. Zero organic waste to rural areas coupled with prohibitive charges on dumping organic waste are the tools to turn the perception into a reality.
As organic coconut farmers, we target zero waste in our farms. That’s the reason why we are now into vermicasting or vermicmposing in which our main substrate is the coconut husk and the coconut pit. We also use the waste from the processing of Virgin Coconut Oil (VCO) as our substance that is acted upon by an enzyme or ferment.
On many organic farms, the basic composting ingredients are manure generated on the farm and bedding. Straw and sawdust are common bedding materials. But in our farm, we used coconut husk and coconut pit. The amount of manure on a livestock farm such as the goat and cow manures are often determined by cleaning schedules, land availability, and weather conditions.
Since compost is a key ingredient in organic farming, it simply requires making a heap of wetted organic matter like leaves, food waste and animal manure. Modern, method of composting is a closely monitored process with measured inputs of water, air, and carbon- and nitrogen-rich materials. The decomposition process is aided by shredding the plant matter, adding water and ensuring proper aeration by regularly turning the mixture. Worms and fungi further break up the material. Aerobic bacteria and fungi manage the chemical process by converting the inputs into heat, carbon dioxide and ammonium. The ammonium is the form of nitrogen (NH4) used by plants. When available ammonium is not used by plants it is further converted by bacteria into nirates (NO3) through the process of nitrification.
Compost can be rich in nutrients. It is used in gardens, landscaping, horticulture and agriculture. The compost itself is beneficial for the land in many ways, including as a soil conditioner. a fertilizer, addition of vital humus, and as a natural pesticide for soil.
Composting organisms require four equally important ingredients to work effectively:
- Carbon - for energy; the microbial oxidation of carbon produces the heat, if included at suggested levels. High carbon materials tend to be brown and dry.
- Nitrogen – to grow and reproduce more organisms to oxidize the carbon. High nitrogen materials tend to be green (or colorful, such as fruits and vegetables) and wet.
- Oxygen - for oxidizing the carbon, the decomposition process.
- Water – in the right amounts to maintain activity without causing anaerobic conditions.
Certain ratios of these materials will provide beneficial bacteria with the nutrients to work at a rate that will heat up the pile. In that process much water will be released as vapor and the oxygen will be quickly depleted, explaining the need to actively manage the pile.
Compost is generally recommended as an additive to soil supplying humus and nutrients. It provides a rich growing medium, or a porous, absorbent material that holds moisture and soluble minerals, providing the support and nutrients in which plants can flourish. Compost can be tilled directly into the soil or growing medium to boost the level of organic matter and the overall fertility of the soil. Compost that is ready to be used as an additive is dark brown or even black with an earthy smell.
Thus, vermicasting or vermicomposting is one of the solutions of zero waste management aside from recycling of nonbiodegradable materials.