Natural greenhouse: A biologically engineered, low-cost and climate-resilient protected cultivation system

Protected cultivation has emerged as an important approach for enhancing crop productivity, quality, and income in Indian agriculture. However, the widespread adoption of conventional polyhouse technology remains limited due to its high capital cost, dependence on synthetic materials, recurring energy requirements, vulnerability to extreme weather events, and short functional lifespan. Therefore, a farmer-led, field-validated and biologically-engineered natural greenhouse has been developed and demonstrated to farmers at Maa Danteshwari Herbal Farms, Kondagaon, Bastar, Chhattisgarh, India. The natural greenhouse is based on a multi-tier living architecture integrating a fast-growing nitrogen-fixing tree species, locally known as Australian teak (Acacia spp.), with a high-yielding black pepper variety (MDBP-16). The system functions as a self-regulating protected cultivation unit, creating a favourable microclimate through canopy-mediated light diffusion, temperature moderation, moisture conservation, and continuous organic nutrient cycling. Unlike conventional polyhouses, it operates without plastic structures, artificial climate control, or external energy inputs. It cost, approximately ₹ 1.0-1.5 lakh per acre, compared to nearly ₹ 40 lakh per acre for a standard polyhouse. The natural greenhouse remains productive for 25–30 years. Independent scientific validation by senior scientists of the ICAR-Indian Institute of Spices Research (IISR), Kozhikode, Kerala, and its regional centre at Madikeri, Karnataka, confirmed black pepperyields of 8-10kg dry berries pervine, farexceedingthenational average of 1.5-2.0kg. In addition to annual crop income, the system generates long-term timber value, enhances soilhealth, and contributes to carbon sequestration. The study establishes the natural greenhouse as a scientifically credible, economically viable, and ecologically regenerative alternative to conventional protected cultivation, with significant potential for replication in suitable agroclimatic regions globally