Polyhouse economics: the numbers that decide whether to build
Protected cultivation works, on the right crop, with the right market. The structure is the small decision; the marketing channel is the large one.
A naturally ventilated polyhouse on a quarter acre costs somewhere between ₹8 and ₹12 lakh to build before a single plant goes in. Subsidy schemes cover a substantial share in most states, and the paperwork takes months. Before any of that, three numbers decide whether the structure will pay.
1. Does the crop earn a protected-cultivation premium
Yield inside a polyhouse rises three to five times over open field for the right crop. That alone does not justify the capital. What justifies it is a price premium for quality and for arriving out of season.
- Coloured capsicum — 4–5x yield, strong premium, established demand from hotels and retail chains.
- Cherry and gourmet tomato — strong premium, but demand is concentrated in cities.
- Cucumber, parthenocarpic varieties — very fast cycle, high yield, thin premium.
- Cut roses and gerbera — highest returns, highest skill requirement, and a cold chain you must arrange yourself.
- Ordinary tomato, chilli, brinjal — yield rises, price does not. The structure does not pay back.
2. Can you reach a buyer who pays the premium
This is the number that sinks most polyhouses, and it is decided before construction, not after the first harvest.
Coloured capsicum at the local mandi fetches close to the price of green capsicum, because that is what the local buyer knows. The premium exists in city wholesale, retail chains and hotel supply — all of which require volume consistency, grading and a delivery arrangement.
Have the channel identified and a rough understanding in place before you build. A quarter-acre polyhouse produces four to six tonnes of capsicum a year. That is a lot to place if you have not thought about where it goes.
3. Does polyhouse cash flow survive eighteen months
Illustrative figures for a quarter-acre naturally ventilated polyhouse growing coloured capsicum, at 2026 costs:
| Item | Amount |
|---|---|
| Structure, fan-pad-free, with drip | ₹9,50,000 |
| Subsidy, typical state share | −₹4,75,000 |
| Planting material and media, per cycle | ₹45,000 |
| Inputs and labour, per cycle | ₹85,000 |
| Yield, 10-month cycle | 5,000 kg |
| Realisation at ₹55/kg net of commission | ₹2,75,000 |
| Gross margin per cycle | ₹1,45,000 |
On those numbers the net capital is recovered in a little over three cycles — call it three and a half years including the establishment gap. That is a reasonable return, and it is entirely dependent on the ₹55 realisation holding. At ₹35, which is what the local mandi will pay, it never pays back.
What a polyhouse budget usually leaves out
- Polythene replacement — the sheet is a consumable, not part of the structure. Budget ₹80,000 every three to four years.
- Insect netting repair — one tear and whitefly is inside, along with leaf curl virus. Inspect monthly.
- Water quality — polyhouse crops are grown on drip and fertigation. Water above 1.5 dS/m electrical conductivity needs treatment, which is a separate cost.
- Skilled labour — pruning, training and pollination in capsicum and tomato need a trained hand. This is not the same labour as an open field.
- Your own time — a polyhouse needs daily attention. Two days unattended in May can cost a cycle.
Build the market first, then the structure. It is the only order that works.
The intermediate option
A shade-net house costs roughly a fifth as much, gives a smaller yield gain, and works well for nursery raising, leafy vegetables and hardening. For a farmer who has not grown under protection before, one season in a shade net teaches most of what the polyhouse will demand — at a fraction of the risk.
Further reading: the National Horticulture Board publishes the current subsidy pattern for polyhouse and protected cultivation.
