How can winter greenhouses better protect against frost and prevent greenhouse vegetables from freezing in cold weather? Based on the experience of recent years, the author has summarized some anti-freezing experiences for reference by farmers.

 

    First, take reinforcement measures. Cooling rain and snow, often accompanied by strong winds. When encountering wind and snow, you should carefully check the area where the shed is easy to loosen and take reinforcement measures. For example, to strengthen the laminating line, fix the southern end of the laminating line on the underground anchor, tie the stone or sandbag at the north end, and fix it outside the north wall to adjust the tightness of the laminating line at any time. The damaged part of the agricultural film should be repaired in time to prevent the wind and snow from blowing into the shed.

 

    Second, timely coverage is increased. Cool down the weather, cover it in advance in the afternoon, and maintain the sealing of the greenhouse film. In rain and snow, the insulation and the grass should also be covered with a film to prevent rain and snow from getting wet and quilt. The old shed wall has poor thermal insulation performance, and can be stacked with grass hoes or crop stalks at the bottom of the back wall of the greenhouse to prevent wind and wind.

 

    Third, timely removal of snow on the shed. In the rain and snow weather, the snow on the shed should be removed in time to prevent the snow from the scaffolding from collapsing the greenhouse bracket. Do a good job of clearing the ditch on both sides of the greenhouse in time, and remove it when there is snow.

 

    Fourth, temporary heating. When the daytime temperature in the greenhouse is lower than 15 °C and the nighttime temperature is lower than 5 °C, cold damage or freezing damage may occur. Temporary heating measures should be taken at night to supplement the heat manually. Several coal ball furnaces can be placed in the shed to increase the temperature inside the shed. But pay attention to prevent carbon dioxide poisoning, the greenhouse should be ventilated first, then enter the person.

 

    Fifth, take a light water pouring, the method of dark irrigation under the membrane. In winter, not only is the temperature low, but the ground temperature is also low, such as excessive watering, and first, the ground temperature drops. The second is to cause poor soil ventilation, which directly affects the activity and absorption function of vegetable roots. The use of small water droplets under the membrane can not only meet the water needs of vegetables, but also not excessively reduce the ground temperature. In order to improve the ground temperature, corn stalks can be laid on the walkway, which can protect the ground temperature and reduce the air humidity in the shed, which is beneficial to the root growth of vegetables.

 

    Six, more light and flexible ventilation. In the case of continuous rain and cool weather, the grass curtain or insulation should not be covered during the day, so that the vegetables are in a dark environment, and the sand and dust on the greenhouse film are cleaned in time. Do not water or spray pesticides on cloudy days. When cooling and cloudy, due to the lack of light, the dark environment of the day will cause yellowing of vegetables. In order to increase the light, the straw curtain should be uncovered every day, and the reflective film will be suspended on the wall in the north of the greenhouse to make vegetables. It is exposed to scattered light to maintain the formation of chlorophyll.

 

    Seven, master the skills of fertilization. Avoid excessive application of high-nitrogen and high-potassium fertilizer during cooling, especially with caution, such as potassium nitrate, appropriate supplement of microbial fertilizer and fish protein organic fertilizer, foliar spray of Pridden fish protein and potassium dihydrogen phosphate, It can increase the stress resistance of crops and improve the cold resistance and frost resistance of plants.

 

    ( Source: Gansu Farmers' Report )