Ultra violet stabilized low density poly ethyleneī. The greenhouse can also be classified based on type of structures, type of glazing, number of spans, environmental control etc. Expensive greenhouses with fully automatic Rs.2000 to Rs.3500/m2 Medium cost greenhouse with pad and fan system Rs.800 to Rs.1100/m2ģ. Less expensive greenhouse without fan and pad Rs.300 to 500/m2Ģ. To overcome some of the difficulties in medium-tech greenhouse, a hi-tech greenhouse where the entire device, controlling the environment parameters, are supported to function automatically.ġ. These greenhouses are suitable for dry and composite climatic zones. As these system are semi-automatic, hence, require a lot of attention and care, and it is very difficult and cumbersome to maintain uniform environment throughout the cropping period. Evaporative cooling pads and misting arrangements are also made to maintain a favourable humidity inside the greenhouse. Exhaust fans with thermostat are provided to control the temperature. Whole structure is firmly fixed with the ground to withstand the disturbance against wind. The canopy cover is attached with structure with the help of screws. This type of greenhouse is constructed using galvanized iron (G.I) pipes. Greenhouse users prefers to have manually or semiautomatic control arrangement owing to minimum investment. This type of greenhouse is mainly suitable for cold climatic zone. Otherwise, inside temperature is increased when all sidewalls are covered with plastic film. Such structure is used as rain shelter for crop cultivation. The temperature can be reduced during summer by opening the side walls. Even light intensity can be reduced by incorporating shading materials like nets.
Simple techniques are, however, adopted for increasing or decreasing the temperature and humidity. Unlike conventional or hi-tech greenhouses, no specific control device for regulating environmental parameters inside the greenhouse are provided. The ultra violet (UV) film is used as cladding materials. Low cost greenhouse is a simple structure constructed with locally available materials such as bamboo, timber etc.
However, environmental control can also include cooling to mitigate excessive temperatures, light control either shading or adding supplemental light, carbon dioxide levels, relative humidity, water, plant nutrients and pest control.Ĭlassification of greenhouse based on suitability and cost The primary environmental parameter traditionally controlled is temperature, usually providing heat to overcome extreme cold conditions. Greenhouses and other technologies for controlled environment plant production are associated with the off-season production of ornamentals and foods of high value in cold climate areas where outdoor production is not possible. Greenhouse cultivation as well as other modes of controlled environment cultivation have been evolved to create favorable micro-climates, which favours the crop production could be possible all through the year or part of the year as required. Greenhouses are frames of inflated structure covered with a transparent material in which crops are grown under controlled environment conditions. Post harvest handling practices for cut flowers Physiological disorders of greenhouse grown cut flowersġ2. Special horticultural practices in greenhouse productionġ1. Problem management in greenhouse cultivationġ0. Cost estimation for green/polyhouse constructionĩ. Drip irrigation and fertigation systems greenhouse cultivationĨ. Environmental factors influencing greenhouse cultivationħ. Plant growing structures/containers in green house productionĥ. Designs and classification of greenhouseĤ.
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