Smart Timing and Low Tunnel Covering: Enhancing Off-Season Cowpea Yield and Profitability in the Bara Tract of South Gujarat, India

A field experiment was conducted during the spring (rabi) seasons of 2022–23 and 2023–24 at the Agricultural Research Station, Navsari Agricultural University, Tanchha, in a Split Plot Design with three replications, comprising two glazing (covering) materials i.e. UV-stabilized plastic film (50 µ), biodegradable plastic and with an open field (control) in the main plots and five sowing times from the third week of November to the third week of December in sub plots, using the cowpea variety AVCP-1. Results indicated that both glazing material and sowing time significantly influenced yield, while their interaction effects were have had non-significant effects. Biodegradable plastic low tunnels recorded the highest pooled (collective) yield (2.80 kg plot⁻¹), whereas the open field condition produced the lowest (1.85 kg plot⁻¹). Among sowing times, the fourth week of November resulted in the highest pooled (collective) yield (2.87 kg plot⁻¹) compared to the third week of December (1.99 kg plot⁻¹). Economic analysis revealed that the combination of biodegradable plastic low tunnel and sowing in the fourth week of November achieved the highest net income (₹ 2,94,501 ha⁻¹), while the lowest was recorded under the open field with the third week of December sowing (₹ 66,505 ha⁻¹). Hence, the strategic integration of microclimate modifying structures with optimally timed sowing is a proven approach to enhancing yield stability and profitability across diverse agro-climatic zones.