What are the precautions for greenhouse vegetables to survive the winter

1. Strengthen insulation and protect against cold and freezing. The winter climate is cold, with low temperatures and frequent strong winds and temperature drops, so doing a good job of cold protection and insulation to keep vegetables from low-temperature damage is the key to winter greenhouse vegetable management. In practice, multi-layer mulching cultivation techniques are usually adopted, that is, covering the ground with plastic film to increase the heat capacity of the soil; covering the greenhouse film with straw curtains, and then covering the straw curtains with an additional layer of plastic film, which can prevent rain from soaking the straw curtains and effectively raise the indoor temperature.

2. Water lightly with a small amount, and irrigate secretly under the film. In winter, not only is the air temperature low, but the soil temperature is also relatively low. Excessive watering, first, causes the soil temperature to drop, and second, causes poor soil aeration, directly affecting the activity and absorption function of the root system. Adopting small-amount secret irrigation under the film can not only meet the water needs of vegetables, but also will not excessively lower the soil temperature or affect soil aeration, so it can effectively resolve the conflict among soil water, air and heat, which is beneficial to the growth of vegetables. If conditions permit, drip irrigation has an even better effect.

3. Management during consecutive cloudy weather. When encountering continuous cloudy, rainy or snowy weather, the straw curtains should still be uncovered every day to let the vegetables receive scattered light, so as to maintain the normal activity of chlorophyll. Usually, the vegetables can be allowed to receive scattered light for 4 to 6 hours around noon. For vegetables that have already entered the flowering and fruiting stage, attention should be paid to harvesting the marketable fruit early and removing the remaining flowers and fruits.

4. Improve the indoor lighting conditions. In winter, natural light itself is relatively weak, and the light inside the greenhouse is often in a deficient state. Adopting various methods to improve indoor lighting is an important technical measure in winter management. First, a reflective curtain (that is, a kind of aluminized plastic film) should be hung on the north wall of the greenhouse, with its length equal to that of the greenhouse, and the hanging height should preferably be such that the lower edge is 20 cm to 30 cm above the ground. At the same time, dust and accumulated snow on the outer surface of the greenhouse film, as well as water droplets and water mist under the film, should be removed at any time to improve the light transmittance of the greenhouse film.