Cost and return structure for castor-based ericulture on one acre in Assam, at 2025-26
prices, covering four crops in the year from 400 dfls. Labour is costed at ₹ 385 per
man-day (MD).
Plantation establishment cost
| # | বিৱৰণ | একক | পৰিমাণ | হাৰ (₹) | মূল্য (₹) |
| A. Land development |
| 1 | Land development using power tiller | এককালীন | | | 1,500 |
| 2 | Green fencing | এককালীন | | | 2,000 |
| 3 | Pit digging (4,000 pits) | MD | 8 | 385 | 3,080 |
| 4 | Castor seeds | kg | 2 | 200 | 400 |
| উপ-মুঠ | | | | 6,980 |
| B. Cost of inputs |
| 1 | Urea | kg | 54 | 12 | 648 |
| 2 | SSP | kg | 101 | 12 | 1,212 |
| 3 | MOP | kg | 13 | 24 | 312 |
| 4 | FYM / vermicompost @ 0.1 cft per plant | cft | 400 | 10 | 4,000 |
| 5 | Application of inputs, basin formation and cultural operations (three times a year) | MD | 62 | 385 | 23,870 |
| 6 | Plant protection chemicals | এককালীন | | | 1,200 |
| উপ-মুঠ | | | | 31,242 |
| Total establishment cost of plantation | | | | 38,222 |
Rearing costs
| # | বিৱৰণ | একক | পৰিমাণ | হাৰ (₹) | মূল্য (₹) |
| A. Fixed cost |
| 1 | Rearing house (thatched) | No. | 1 | 50,000 | 50,000 |
| 2 | Platform with stand | No. | 4 | 1,800 | 7,200 |
| 3 | Mountage (plastic) | No. | 100 | 80 | 8,000 |
| 4 | Sprayer | No. | 1 | 2,000 | 2,000 |
| Total fixed cost | | | | 67,200 |
| Depreciation on building and equipment @ 10 % | | | | 6,720 |
| B. Variable cost |
| 1 | Silkworm seed (for four crops) | dfls | 400 | 9 | 3,600 |
| 2 | Disinfectants | এককালীন | | | 1,200 |
| 3 | Labour — cleaning and disinfection of rearing house | MD | 4 | 385 | 1,540 |
| 4 | Labour — rearing operations | MD | 112 | 385 | 43,120 |
| 5 | Labour — removal of pupae | MD | 32 | 385 | 12,320 |
| Total variable cost | | | | 61,780 |
| Total cost of silkworm rearing (depreciation 6,720 + variable 61,780) | | | | 68,500 |
Revenue and returns
| # | বিৱৰণ | একক | পৰিমাণ | হাৰ (₹) | মূল্য (₹) |
| 1 | Sale of cocoons @ 10 kg per 100 dfls | kg | 40 | 900 | 36,000 |
| 2 | Sale of pupae @ 70 kg per 100 dfls | kg | 280 | 600 | 1,68,000 |
| Total return | | | | 2,04,000 |
| Total cost (plantation 38,222 + rearing 68,500) | | | | 1,06,722 |
| Net return | | | | 97,278 |
| Benefit–cost ratio | | | | 1.91 |
Read this before quoting the ratio. Pupae account for about 82 % of gross
revenue in this model, so the return depends heavily on an assured outlet for pupae at
₹ 600 per kg. Where pupae cannot be sold, the unit realises only the cocoon revenue
and the benefit–cost ratio falls below unity. Wages and fertiliser prices vary over
time with economic, political and environmental factors.