Vegetable greenhouse cultivation temperature and humidity control
temperature control. 1. Appropriate temperature for vegetable growth generally needs 20°C-30°C during daytime, 10°C-20°C during nighttime, 5°C and below 40°C growth inhibition, some crops have high temperature requirements, such as watermelon and melon. 25°C-30°C. The growth stopped at 10°C and the freezing injury occurred at 5°C. 2. Specific methods for temperature regulation in the shed: (1) In winter production, multiple cover cultivation techniques are generally adopted: covering the ground film on the ground; covering the shed film on the shed film, and then adding a layer of plastic film on the turf curtain. In case of strong cooling weather, temporary heating measures shall be taken: multiple coal cake stoves shall be set up in the shed for warming, and electric heating lines and diesel heaters may be used to warm the equipment. (2) In summer, the temperature in the shed is very high. All the vents around the greenhouse must be opened. If the temperature is too high, the shade can be covered on the top of the greenhouse for cooling. In sunny days during the day, timely measure the temperature in the shed. Once the temperature rises above 30°C, immediately open the vents on both sides for ventilation and adjust the vents so as to stabilize the temperature in the shed to 25°C-30°C. (3) Adopting lightening measures to increase light intensity and prolong lighting time: Select agricultural film with high light transmittance, and clean the film to ensure the cleanness of the agricultural film; cover the white plastic film; suspend the light curtain on the back wall; timely pruning and picking Leaves to enhance the light transmission in the field. Humidity control. Indoor air humidity adjustment: 1. Minimize watering during growth period, prevent watering during the growth period, lower the ground temperature, increase air humidity, and if watering is required during the growth period, open the canal to fill the small water and avoid flooding. 2. Covering the drip-free membrane; irrigating the soil in the shed, using a plastic hose under the mulching film to spray irrigation, and drip irrigation facilities can be used if necessary. 3. Use large and small rows as much as possible. 4. Timely cultivating loose soil after watering. 5. Under the premise of ensuring the appropriate temperature, timely ventilation, discharge moisture; cold water season, should be selected in the sunny morning. Immediately after the watering, the enclosure was sealed and the temperature was increased. Wait until noon and afternoon to increase ventilation and remove moisture. Through the above measures, the air humidity in the shed can be greatly reduced. Lighting control. 1. When planting different types of vegetables in greenhouses, the principle of “lower height from the north to the south†should be followed, so that the plants can be staggered and arranged in an orderly manner, minimizing mutual obstruction. Transplanting the same kind of vegetables, and strive for the same size of the seedlings, so that the plants grow neatly and reduce shading between the plants. At the same time, it is better to do planting in the north and south to make it as sunny as possible. 2. Keep the shed membrane clean. Water droplets, dust, and other debris on the film will reduce the light transmittance by about 30%. After the new film is used for 2 days, 10 days and 15 days, the lighting in the shed will be reduced by 14%, 25%, and 28% in turn. Therefore, it is necessary to regularly clean, wash the dust, dirt and water droplets on the surface of the house, and keep the surface of the film clean to increase the transparency of the film. Snow should also be cleared of snow in a timely manner. 3. Use drop-free film. The use of a drip-free membrane shed can increase the light intensity in the shed and increase the temperature of the shed. 4. Reasonably uncover the straw curtain. Under the premise of doing a good job of insulation work, appropriate removal of the straw curtain used for heat preservation and delaying of the curtain curtain will be carried out. Generally, the curtain will be uncovered 0.5-1 hours after the sun comes out, and the curtain will be covered half an hour before the sun goes down. Especially in the rainy days when it rains, it is necessary to properly uncover the sun's scattered light. 5. Set the light curtain. With a 2-meter-wide, 3 meter-long aluminized film reflector, hanging on the north side of the greenhouse to make it perpendicular to the ground, it can add 40% light to the ground and increase the temperature of the shed by 3°C-4°C. In addition, laying silver-gray film on the ground can also increase the light intensity between plants. 6. Do a good job of planting. Timely pruning, hiccups, vines, old leaves and other field management are conducive to ventilation in the shed. Cup Kn95 Mask,Kn95 Approved Cup Mask,Kn95 Protective Cup Mask,Kn95 Protective Cup Face Mask Ningbo Autrends Prevention Products Co., Ltd , https://www.autrendsafety.com