Economic analysis of protected cultivation of vegetables under naturally ventilated polyhouse

Abstract:

Ibrahim Ozturk noted in a 2016 address to the Turkish Agricultural Congress that the central economic question for Turkish vegetable farming is no longer about productivity per hectare - which has been rising - but about returns per cubic metre of water and per day of skilled labour under rising climate volatility. This research evaluated the economics of naturally ventilated polyhouse cultivation against traditional open-field vegetable farming for four crops - capsicum, tomato, cucumber and coloured bell pepper - in the Adana province of Cukurova. Primary data were collected between April 2021 and March 2024 from 48 polyhouse farms (of 1 000 to 2 000 m² area each) and a matched sample of 48 open-field farms. Discounted cash flow analysis was applied with an 8.5 percent discount rate over a ten-year horizon. Coloured capsicum emerged as the most profitable crop under polyhouse, with net present value of TRY 1,140,000 per 1 000 m², benefit-cost ratio of 2.38, internal rate of return of 34.6 percent and payback period of 3.8 years. Tomato and cucumber followed closely. Yields under polyhouse were 2.4 to 2.9 times higher than open-field, and price premiums of 18 to 34 percent were captured because the harvest extended across lean months when open-field supply thins. Sensitivity analysis showed that the economics remain positive under a 20 percent drop in yield, a 15 percent rise in input cost or a 25 percent cut in price premium. The analysis supports naturally ventilated polyhouse cultivation as the most attractive intensification option currently available to mid-size Cukurova farmers holding reliable irrigation.