sivadeepam
New Member
Hi, need to know abt green house farming, like minimum area required for costruction of green house, suitable crops for cultivation and cost of project etc...
Hi
Green house technology provides a controlled and favourable environment for the crops to grow in all seasons. The technology saves crops from cold in winter, from heat in summer and from rain in monsoon. Unlike European countries, in India the technology is primarily used in cooling off the environment, as normal temperature is high.
Green House technology is more suited to vegetables crops (such as tomato, brinjal, cauliflower, capsicum, cabbage, chillies, ladies finger, spinach etc.), flowers (like rose, gerbera, carnation etc) and nursery for all vegetable crops, because of their small life-span. This technology is mainly suitable for commercial farming, as it requires investment in setting up the entire framework. It involves a structure similar to a house, in which only sunlight is allowed to enter. It has mainly two parts, first is a frame or the basic structure made of galvanized iron pipes, bamboo, woods and iron rods, and the second is the cladding or covering material made of glass and plastic films.
Investment is a major factor in the setting up a green house. Hence based on the cost and investment, green house can be categorized in three groups namely low cost green house, medium cost green house and hi-tech green house.
Low-cost Green House : It is a zero-energy chamber made of polythene sheet of 700 guage supported on bamboos with rope and nails. Its size depends on the purpose of its utilization and availability of space. It has one opening which is kept open for 1-2 hour during the day, especially in the morning to reduce the level of humidity inside. The temperature within polyhouse increases by 6-10o C more than outside. In Ultra Violet (UV) stabilized plastic film covered, pipe framed polyhouse, the day temperature is higher and night temperature lower than the outside. The solar radiations entering the polyhouse is 30-40% lower than that reaching the soil surface outside.
Medium-cost Green House : With a slightly higher cost, an arc-shaped polyhouse (green house) can be framed with GI pipe of 15 mm bore. This polyhouse has a single layer covering Ultra Violet – stabilized polythene of 800 gauge. Thermostatically controlled exhaust fans are used for ventilation. Cooling pad is used for humidifying the air entering the polyhouse. The polyhouse frame and glazing material have a life span of about 20 years and 2 years respectively.
Hi-tech Green House : In such type of green houses, temperature, humidity and light are automatically controlled. These are indicated through sensors or signal receivers. Sensor measures the variables, compare the measurement to a standard value and finally recommends to run the corresponding device. For example, temperature control system consists of temperature sensor, heating/cooling mechanism and thermostat-operated fan. Similarily, relative humidity is sensed through optical tagging devices. Boiler operation, irrigation and misting systems are operated under pressure sensing system. This modern structure is highly expensive and requires qualified operators for maintenance, care and precautions.
Regards
Ashwini