Vegetable defense against late spring frost
Frost in late spring usually occurs in the middle or late April, causing frost on the surface of growing vegetable plants in the field. According to the author's practical experience, the measures for preventing cold spells in spring are introduced as follows: First, the low-temperature hardening seedlings in the seedlings Qi Qi, the seedbed to be ventilated, and gradually increase the ventilation with warmer weather, the seedlings for low-temperature exercise, in order to improve the cold resistance of seedlings to adapt to the outdoor low temperature environment. Second, increase the number of facilities to increase protection facilities can take two ways: First, the erection of wind barriers. The wind barrier has a blocking effect on the cold air and prevents the surface from further cooling. The second is planting trenches and covering the mulch. When planting vegetables in early spring, the ditching planting method can be adopted, and the ditch depth requires more than the height of the seedlings, and then the dura can be covered with a plastic film. Third, temporary warming protection of production, in the cold current, in the nursery shed or production shed by means of building a simple coal stove or install lights to temporarily warm, in order to increase the temperature inside the shed to prevent freezing damage. IV. Watering wells When the strong cold air passes, the weather is clear, there is no wind or breeze at night, and the temperature drops rapidly, especially when the local surface temperature falls below 0°C. When frost occurs, a large amount of well water can be poured on the ground to a large extent. Increase the ground temperature. This method can increase the ground temperature from 0 °C to 8 °C, to avoid frost. V. Lighting fumes In frost nights, fuming in the fields can effectively reduce or avoid frost disasters. However, there are two things to note: First, the pyrotechnics should be dense enough to allow the smoke screen to cover the whole park; second, the lighting time should be appropriate. It should be lit in the upper wind direction, from midnight to 2:00 in the morning until sunrise. There is a smoke screen covering the ground. This works best. 6. Appropriate amount of water spray Before the frost occurs, spraying the water on the surface of the plant with a sprayer can slow down the body temperature and increase the content of water vapor in the atmosphere. The water vapor condenses and releases heat to mitigate frost damage. 7. Timely cultivator cultivators before frost can reduce frost damage. Because the temperature in the spring rises gradually, after the clay is loosened, the solar thermal energy can be better absorbed and stored. Once the frost comes, the frost can be alleviated because a part of the heat has accumulated in the soil. 128 Slice CT,128 Slice CT Ge,Spiral CT Scanner,128 Slice Cardiac CT Scan MinFound Medical Systems Co., Ltd , https://www.minfoundmed.com