A polytunnel is a tunnel made of polyethylene. The polytunnels/polyhouses can also protect crops from intense heat, bright sunlight and strong winds. The interior heats up because incoming solar radiation from the sun warms plants, soil, and other things inside the building faster than heat can escape the structure. Air warmed by the heat from hot interior surfaces is retained in the building by the roof and wall. Temperature, humidity and ventilation can be controlled by equipment fixed in the polytunnel.
Its basic advantages includes protection from excess rainfall, crops are grown all year around, Production of uniform quality crops, Protection from birds, animals and human activities, Productivity is 8 to 10 times higher, Management of insect pests, diseases and weeds is easier, Required minimum inputs such as labor, water and fertilizers. Organic farming is easier and export oriented production is possible under these structures.