Vermicompost - Production and Practices

Vermicomposting is a method of preparing enriched compost with the use of
earthworms. It is one of the easiest methods to recycle agricultural wastes and to
produce quality compost. Earthworms consume biomass and excrete it in digested
form called worm casts. Worm casts are popularly called as Black gold. The casts
are rich in nutrients, growth promoting substances, beneficial soil micro flora and
having properties of inhibiting pathogenic microbes.
Vermicompost is stable, fine granular organic manure, which enriches soil quality by
improving its physicochemical and biological properties. It is highly useful in raising
seedlings and for crop production. Vermicompost is  becoming popular as a major
component of organic farming system.
Vermicomposting materials
Decomposable organic wastes such as animal excreta, kitchen waste, farm residues
and forest litter are commonly used as composting materials. In general, animal dung
mostly cow dung and dried chopped crop residues are the key raw materials. Mixture
of leguminous and non-leguminous crop residues enriches the quality of
vermicompost.
There are different species of earthworms viz.  Eisenia foetida  (Red earthworm),
Eudrilus eugeniae  (night crawler),  Perionyx excavatus etc. Red earthworm is
preferred because of its high multiplication rate and thereby converts the organic
matter into vermicompost within 45-50 days. Since it is a surface feeder it converts
organic materials into vermicompost from top.
Important characteristics of red earthworm (Eisenia foetida)
Characters    Eisenia foetida
Body length   3-10cm
Body weight   0.4-0.6g
Maturity   50-55days
Conversion rate  2.0 q/1500worms/2 months
Cocoon production  1 in every 3 days
Incubation of cocoon  20-23days
Types of vermicomposting
The types of vermicomposting depend upon the amount of producton and composting
structures. Small-scale vermicomposting is done to meet the personal requirement and
farmer can harvest 5-10 tonnes of vermicompost annually. While, large-scale
vermicomposting is done at commercial scale by recycling large quantity of organic
waste with the production of more than 50 – 100 tonnes annually
Methods of vermicomposting
Vermicromposting is done by various
methods, among them bed and pit
methods are more common.
Bed method : Composting is done on the
pucca / kachcha floor by making bed (6x2x2 feet size) of organic mixture. This method is easy to maintain and to practice
(Fig.1).
Pit method: Composting is done in the
cemented pits of size 5x5x3 feet. The unit is
covered with thatch grass or any other locally
available materials. This method is not
preferred due to poor aeration, water logging at
bottom, and more cost of production (fig.2)
Process of vermicomposting
Following steps are followed for vermicompost preparation
• Vermicomposting unit should be in a cool, moist and shady site
• Cow dung and chopped dried leafy materials are mixed in the proportion of 3: 1
and are kept for partial decomposition for 15 – 20 days.
• A layer of 15-20cm of chopped dried leaves/grasses should be kept as bedding
material at the bottom of the bed.
• Beds of partially decomposed material of size 6x2x2 feet should be made (fig.3).
• Each bed should contain 1.5-2.0q of raw material and the number of beds can be
increased as per raw material availability and requirement.
• Red earthworm (1500-2000) should be released on the upper layer of bed (fig.4).
• Water should be sprinkled with can immediately after the release of worms (fig.5)
• Beds should be kept moist by sprinkling of water (daily) and by covering with
gunny bags/polythene (fig.6)
• Bed should be turned once after 30 days for maintaining aeration and for proper
decomposition.
• Compost gets ready in 45-50 days (fig.7).
• The finished product is 3/4
th
 of the raw materials used.
Harvesting
When raw material is completely decomposed it appears black and granular. Watering
should be stopped as compost gets ready. The compost shout be kept over a heap of
partially decomposed cow dung so that earthworms could migrate to cow dung from
compost (fig.7). After two days compost can be separated and sieved for use (fig.8). Preventive measures
• The floor of the unit should be compact to prevent earthworms’ migration into
the soil.
• 15-20 days old cow dung should be used to avoid excess heat.
• The organic wastes should be free from plastics, chemicals, pesticides and
metals etc.
• Aeration should be maintained for proper growth and multiplication of
earthworms.
• Optimum moisture level (30-40 %) should be maintained
• 18-25
o
C temperature should be maintained for proper decomposition.
Nutrient content of vermicompost
The level of nutrients in compost depends upon the source of the raw material and the
species of earthworm. A fine worm cast is rich in N P K besides other nutrients.
Nutrients in vermicompost are in readily available  form and are released within a
month of application.
Nutrient Analysis of Vermicompost
 Parameters   Content
 pH    6.8
 OC%    11.88
 OM%    20.46
C/N ration   11.64
Total Nitrogen (%)  1.02
Available N (%)  0.50
Available P (%)  0.30
Available K (%)  0.24
Ca (%)    0.17
Mg (%)   0.06
Advantages
There are many advantages of vermicompost :
• It provides efficient conversion of organic wastes/crop/animal residues. • It is a stable and enriched soil conditioner.
• It helps in reducing population of pathogenic microbes.
• It helps in reducing the toxicity of heavy metals.
• It is economically viable and environmentally safe  nutrient supplement for
organic food production.
• It is an easily adoptable low cost technology.
Doses
The doses of vermicompost application depend upon the type of crop grown in the
field/nursery. For fruit crops, it is applied in the tree basin. It is added in the pot
mixture for potted ornamental plants and for raising seedlings. Vermicompost should
be used as a component of integrated nutrient supply system.
 Crops   Dose/rate
 Field crops  5-6t/ha
 Fruit crops  3-5kg/plant
 Pots   100-200g/pot
Benefit
Vermicomposting is a highly profitable venture for farmers having dairy units. The
approximate cost and benefit under different scale of production is given below.
Scale  App.cost per   App.benefit per Cost/benefit ratio
                         annum (Rs)     annum (Rs)
 Small  52,000       90,000        1 : 1.73
 Medium 1.0 lakh      1.85 lakh        1 : 1.85
 Large  2.25 lakh      4.5 lakh        1 : 2.0
Published by
ICAR Research Complex for NEH Region,
Umiam – 793 103, Meghalaya
For Further information contact
Joint Director,
ICAR Research Complex for NEH Region, Mizoram Centre
Kolasib – 796081, Mizoram