Management methods for greenhouse vegetables to overwinter safely

Pay attention to heating and insulation inside the greenhouse. For greenhouses with fewer straw curtains, a thinner back wall and poor insulation, increase the covering thickness of straw curtains, use double-layer curtains as much as possible, and add rain- and snow-proof plastic film over the straw curtains to keep them dry. If the temperature inside the greenhouse is below 6°C, use the method of burning a stove to add heat; for fruit vegetables such as cucumbers and tomatoes, the main focus is on protecting the roots, protecting the seedlings and keeping them alive.

Pay attention to management during consecutive cloudy days. When consecutive cloudy days occur, as long as the temperature is not very low, the straw curtains should be uncovered; if the sun comes out for a short time, the temperature inside the greenhouse will rise. Hanging a reflective screen on the back wall inside the greenhouse will also help increase light and raise temperature on cloudy days. Keep the nighttime room temperature no lower than 10°C, strive to store more heat in the back wall after sunny days, and control the daytime temperature at 25°C-28°C; when it is above 30°C, ventilate promptly. When there are many cloudy days in winter, plastic film should be laid early, which can raise the ground temperature and reduce the occurrence of low-temperature freezing damage.

Pay attention to management after a long period of cloudy weather suddenly turns clear. After long periods of cloudy and foggy weather, once a sunny day appears, transpiration in the vegetables will strengthen, root absorption cannot keep up, and after the sunny day a large number of seedlings may die. When this kind of weather occurs, first pay attention to covering the straw curtains to prevent seedling scorch. After it turns clear, the temperature rises quickly and the seedlings will wilt sharply; from around 10 a.m., watch for changes in the seedlings and take measures such as moderately covering the straw curtains and spraying clear water inside the greenhouse. Second, after a sunny day, water as little as possible; the root system must regain vitality before watering, otherwise it is easy to cause root rot and seedling death. If watering and fertilizing are needed, water lightly and apply quick-soluble fertilizer with the water, and the concentration should be low. Finally, after a sunny day, use root-promoting agents to drench the roots and spray multi-element micro-fertilizer on the leaves to make up for insufficient root absorption.

Management during snowy weather. If snow falls during the day, be sure to roll up the straw curtains first, and immediately clear the snow on the greenhouse film after the snow stops. For parts of the greenhouse with a slope that are difficult to clear, gently scrape downward with a smooth wooden stick, trying not to cut the greenhouse film. If snow falls at night, pay even more attention to promptly removing snow from the straw curtains; wrap the straw curtains with plastic film in advance to prevent the straw curtains from absorbing water, otherwise the greenhouse body will bear too much weight and the arch frame may twist or even collapse.

Management during windy weather. When the greenhouse film bulges, immediately tie the film-pressing lines tightly or lower part of the straw curtains to press down on the middle of the front roof of the greenhouse. If strong wind occurs at night, it is best to lay a layer of straw curtains horizontally across the front bottom edge of the greenhouse, then press them firmly with stones.