Should vegetables be covered with film when the weather is 12 degrees?
Do not cover the dishes in 12 degree weather.
After the beginning of December, various regions have entered the frost period, which is generally called "frost day" by farmers. If the seedlings are not well prepared for frost protection during this period, they will easily suffer frost damage when encountering a relatively heavy (cold) frost. This usually manifests as water damage to the leaves. After a few days, if the air is dry, they will become dry. If the air humidity is high, Mildew or disease occurs in large quantities. Therefore, everyone must do a good job in cultivating seedlings during this period.
When training seedlings, the principle of "less ventilation on cloudy days, more ventilation on sunny days, and no ventilation on rainy days" should be followed to ensure that the seedlings are strong, neat, and not leggy. Generally, the temperature inside the film should be controlled at about 20°C on sunny days. When it exceeds 25°C, the film must be removed to ventilate and cool down until there are no water droplets on the inner surface of the film. You can open both ends or both sides of the shed and cover it with film before 4 p.m.
On cloudy days, small-scale ventilation can be carried out from 12 am to 2 noon; on rainy days, there is generally no need to open the greenhouse. If it rains for more than three consecutive days, you can open both ends of the membrane to ventilate for 2-4 hours at noon, but do not let the rainwater get onto the seedling bed. Even if the daily average temperature is lower than 12°C and there is no ventilation for three consecutive days, the film should be removed at noon for 2-3 hours, but the time should not be too long.
The role of seedling training
Miao training refers to artificially "creating" a harsh environment for the seedlings during their seedling stage, so that the seedlings can better adapt to their growth environment. a measure. In the case of seedlings raised in protected areas, measures such as ventilation, cooling, and appropriate water control are usually taken to forcibly exercise the seedlings so that they can quickly adapt to the adverse environmental conditions in the open field after planting, shorten the time for seedlings to slow down, and enhance their resistance to low temperatures, strong winds, etc. ability.
The specific method for cultivating seedlings is to strictly control the water content after the temperature gradually decreases - generally no more watering. If it is too dry and wilting, you should choose sunny weather and a small amount of water in the morning. Water; control the growth of seedlings - even in sunny weather, increase ventilation and lower the temperature to avoid excessive growth or too tender stems and leaves.
Enhance light——Under the condition that the plant life can be maintained normally, reduce the covering as much as possible during the day, or use artificial supplementary light. At the same time, you should always pay attention to the local weather forecast. When encountering a cold wave, you should always prepare for cold protection and heat preservation.