Vermicompost can be made almost anywhere in India that has shade, a steady supply of cattle dung and farm waste, and water, and it pays best when you use it on your own farm or sell to nearby farmers and nurseries. As a business, selling in bulk is low-margin: bulk dealers pay roughly ₹3 to ₹5 per kg, so income depends on volume, low cost of dung and a real buyer.

The process is simple: earthworms eat partly decomposed dung and plant waste and turn it into fine castings in about 2.5 months. Most failures come from heat, dryness, flooding, ants and poor feedstock, not from the worms themselves.

Worms to use

  • TNAU lists three species for converting waste: Eisenia fetida (red wiggler), Eudrilus eugeniae (African night crawler) and Perionyx excavatus. Local garden earthworms are not suitable for beds.
  • They breed fast: maturity at about six weeks, then one egg capsule every 7 to 10 days, each giving 3 to 7 worms.
  • TNAU's stocking rate is about 350 worms per cubic metre of bed.
  • Buy starter worms from a KVK, agricultural university or a known unit. Be wary of any seller who sells worms together with a promise to buy your compost back at a fixed price; this has been a common scam. Ask for a written, registered agreement and check whether anyone has actually been paid.

Site, beds and shed

  • Shelter: shade with good air flow, a raised floor that drains, and protection from rain, direct sun, ants, birds and poultry. TNAU costs a temporary shed of 8 x 15 m at about ₹72,000 in its model (older prices, so expect more now).
  • Beds: 75 to 90 cm of material, width not more than 1.5 m so you can work from the sides. Length as the shed allows.
  • Conditions: moisture 40 to 50% and temperature 20 to 30 degrees C, kept up by sprinkling. Heat and dryness are the usual killers of worms, so shade and sprinkling matter.

Feedstock and filling

  • TNAU's ratio is about 320 kg of agricultural waste and 80 kg of cow dung per cubic metre of bed, i.e. roughly 80% waste and 20% dung by weight.
  • Partly decompose the material for about two weeks first so the heat of fresh dung has gone, then add the worms.
  • Good feed: cow, buffalo and goat dung, crop residues, leaves, kitchen waste. Keep out plastic, glass, metal, large amounts of onion, citrus, meat, oil, and anything treated with pesticide.

Cycle and harvest

  • TNAU gives a production cycle of 75 days. When the top layer looks like dark, crumbly tea-leaf castings and the feed is gone, stop watering for a few days, heap the compost in cones so the worms move down, scrape the top, and sieve.
  • The same TNAU model shows 30% recovery of finished compost from the input material. A cubic metre of bed holds about 400 kg of input, so expect about 120 kg of compost per cubic metre per cycle.
Step (one bed 3 m x 1.5 m x 0.75 m)WorkingResult
Bed volume3 x 1.5 x 0.753.4 m3
Feed per cycle3.4 x 400 kgabout 1,350 kg
Worms to stock3.4 x 350about 1,200
Compost per cycle1,350 x 30%about 400 kg
Cycles per year365 / 75about 4.9
Compost per bed per year400 x 4.9about 2 tonnes

Using vermicompost on your own farm

No single verified ICAR or state-university dose that fits all crops was found, so follow your soil-health card and KVK advice. Vermicompost is a soil conditioner and a modest nutrient source, not a replacement for a full fertiliser plan on high-yielding crops; see fertilizers. It is most worthwhile for vegetables, flowers, orchards and nurseries, where a few kg per plant or bed is affordable.

Cost and returns

  • Capital cost: the NABARD model project for a 200 tonne per year unit estimates capital cost of roughly ₹1,500 to ₹2,500 per tonne of annual capacity (older figures; large units cost more where machinery and transport are needed). TNAU's 200-tonne model lists first-year capital of ₹6.45 lakh and operating cost of ₹3.68 lakh per year, with a modelled return of 36% IRR. Its prices (cost ₹1.50 per kg, selling ₹2.50 per kg) are old; update them locally.
  • Selling price: market reports give about ₹3 to ₹5 per kg in bulk to dealers, ₹5 to ₹10 per kg for bagged, branded product, and ₹10 to ₹50 per kg on e-commerce for small packs. These are mostly secondary sources and vary by district; check with local nurseries and input dealers.
  • Arithmetic: one 3 m x 1.5 m bed gives about 2 tonnes a year. At ₹5 per kg that is ₹10,000 per bed per year, and at ₹10 per kg ₹20,000. To make 200 tonnes you need about 100 such beds, which gives ₹10 to ₹20 lakh gross on that price range, before dung, labour, water, packing and transport. At ₹3 per kg the gross is ₹6 lakh, which fails to cover costs for many small units.
  • Margins improve if you use your own dung and labour, sell directly to nurseries and farms, or use the compost on your own crops (replacing purchased manure).
💡 Tip: Start with 4 to 6 beds, sell the first batches locally, and expand only when buyers repeat their orders. Many units fail from lack of customers, not poor production.

Quality, registration and subsidy

  • Selling vermicompost as a fertiliser falls under the Fertiliser (Control) Order, which sets minimum quality standards (organic carbon, nitrogen, moisture, particle size and heavy metals). Ask your district agriculture officer what registration or testing you need for the volume you sell, and get your product lab-tested.
  • Quality tips: sieve to a uniform fine texture, keep it moist and shaded in storage and do not mix in soil or sand; adulteration is the main source of buyer complaints.
  • Subsidy: support reported for horticulture under NHM is 50% of cost subject to a maximum of ₹30,000 per beneficiary, per a government statement; the NCOF capital investment subsidy covers larger commercial units (25% for bio-input units up to ₹40 lakh; 33% for fruit and vegetable waste compost units up to ₹60 lakh) but vermi-hatcheries were discontinued in 2010. These rates are from older notifications, so confirm current eligibility at your district horticulture or agriculture office. See subsidy finder, FPO and KCC.

Sources