What to Do When Greenhouse Vegetables Encounter Rain and Snow? Detailed Explanation of Disaster Relief Measures
Disaster Relief Measures for Greenhouse Vegetables in Rain and Snow Weather
The impact of snowfall on greenhouse vegetable production is multifaceted. First, mechanical damage. Due to the weight of snow, excessive accumulation can often crush greenhouses with weak structures. According to estimates, when the snow accumulation depth is about 20 cm, the snow can reach 25 kg per sq m, and the snow pressure on the roof of one mu of greenhouse can reach 13 tons. Such a heavy burden is difficult for simple greenhouses with bamboo and wood structures to support, and damage is very likely. Second, insufficient light. Snowy days have no sunlight to begin with, and in order to keep the greenhouse warm, several layers of straw mats and other coverings must be added outside, making the light inside the greenhouse severely insufficient and photosynthesis impossible. Third, freezing damage. As the saying goes: "It is not cold when it snows, but cold when the snow melts." After snowfall, low temperatures often follow, and improper management can easily cause greenhouse vegetables to suffer freezing damage.
Improve the greenhouse structure Simple greenhouses are easily crushed by accumulated snow, so they should be promptly replaced with greenhouses using reinforced steel and concrete frame structures. If bamboo, wood and plastic pipe frames are used, their load-bearing capacity should be carefully tested, and an arched design should be adopted to enhance support capacity. At the same time, the roof should have a certain slope so that snow does not easily accumulate.
Sweep snow promptly If it snows during the day, cover well with reed-fiber mats, then add straw mats on top, and remove the snow immediately after it stops; if it snows at night, sweep the snow promptly the next morning after it stops to keep the coverings dry. When the snow is especially heavy, whether during the day or at night, sweep it as it falls to prevent excessive accumulation from crushing the greenhouse.
Strengthen the management of coverings After snow, promptly remove the coverings to let the seedlings see light. After continuous overcast and snowy weather followed by a sudden clearing, pay attention to observing changes in the seedlings after removing the coverings. If wilting is found, immediately cover well with reed-fiber mats, uncover again after recovery, cover again if wilting recurs, and repeat this process. After 2~3 days, normal management can be resumed; if they are uncovered and ignored, "seedling collapse" is likely to occur.
Pay attention to ventilation and air exchange If overcast and snowy weather lasts for more than 3 consecutive days, because vegetable respiration consumes more than photosynthesis, a large amount of harmful gases such as carbon dioxide will accumulate in the greenhouse. Take advantage of the higher temperature at noon to ventilate from the top for 1~2 hours.
Make clever use of snow water, turning harm into benefit In melted snow water, the nitride content is 4 times higher than that of the same volume of rainwater, the heavy water content is 1/4 less than that of ordinary water, and the content of toxic and harmful substances such as phenols and mercury is also lower than that of ordinary water. Heavy water is a radioactive substance that strongly inhibits various life processes, hence it is called "dead water." Using snow water instead of ordinary water for seed soaking and watering vegetables can greatly reduce the harm of heavy water and increase vegetable yield. According to experiments, cucumber seeds soaked in snow water have a germination rate 40% higher than usual; watering cucumber seedlings with snow water can double the yield.
Improve the greenhouse structure Simple greenhouses are easily crushed by accumulated snow, so they should be promptly replaced with greenhouses using reinforced steel and concrete frame structures. If bamboo, wood and plastic pipe frames are used, their load-bearing capacity should be carefully tested, and an arched design should be adopted to enhance support capacity. At the same time, the roof should have a certain slope so that snow does not easily accumulate.
Sweep snow promptly If it snows during the day, cover well with reed-fiber mats, then add straw mats on top, and remove the snow immediately after it stops; if it snows at night, sweep the snow promptly the next morning after it stops to keep the coverings dry. When the snow is especially heavy, whether during the day or at night, sweep it as it falls to prevent excessive accumulation from crushing the greenhouse.
Strengthen the management of coverings After snow, promptly remove the coverings to let the seedlings see light. After continuous overcast and snowy weather followed by a sudden clearing, pay attention to observing changes in the seedlings after removing the coverings. If wilting is found, immediately cover well with reed-fiber mats, uncover again after recovery, cover again if wilting recurs, and repeat this process. After 2~3 days, normal management can be resumed; if they are uncovered and ignored, "seedling collapse" is likely to occur.
Pay attention to ventilation and air exchange If overcast and snowy weather lasts for more than 3 consecutive days, because vegetable respiration consumes more than photosynthesis, a large amount of harmful gases such as carbon dioxide will accumulate in the greenhouse. Take advantage of the higher temperature at noon to ventilate from the top for 1~2 hours.
Make clever use of snow water, turning harm into benefit In melted snow water, the nitride content is 4 times higher than that of the same volume of rainwater, the heavy water content is 1/4 less than that of ordinary water, and the content of toxic and harmful substances such as phenols and mercury is also lower than that of ordinary water. Heavy water is a radioactive substance that strongly inhibits various life processes, hence it is called "dead water." Using snow water instead of ordinary water for seed soaking and watering vegetables can greatly reduce the harm of heavy water and increase vegetable yield. According to experiments, cucumber seeds soaked in snow water have a germination rate 40% higher than usual; watering cucumber seedlings with snow water can double the yield.