What are the consequences of forgetting to turn off the air vent when growing vegetables in a greenhouse?

In autumn and winter, many crops cannot grow in cold environments, so greenhouse planting has become a more common planting method now. Because greenhouse cultivation can freely adjust the temperature, it brings more economic benefits to growers. This off-season cultivation also provides convenience for people, who can also eat their favorite vegetables in winter. However, greenhouse planting is not that easy. When planting, since the greenhouse is closed, ventilation is essential. However, some growers believe that the temperature in winter is too low, and ventilation will cause freezing damage to vegetables, so they ignore this aspect. In fact, ventilation in winter is very important, and there are many issues that need to be paid attention to. Let’s talk about it in detail below. How to ventilate a greenhouse in winter

When ventilating a greenhouse in winter, the weather is very important. Growers should choose sunny days to ventilate, and do it in two stages. Open the shed in the morning, and open the upper air vent about 3 cm after an hour. This can discharge the moisture inside and replenish carbon dioxide, creating favorable conditions for photosynthesis. The second time is to wait until the temperature in the shed rises to above 28 degrees, then open the air outlet by 8-10 cm. If it is vegetables with higher temperature requirements, open it to 6-8 cm. The size of the air vent should be determined according to the direction of the wind. If the wind is blowing from the west or west, the wind will enter the shed, causing the temperature inside the shed to drop. The grower should close the air vent at the east end to a smaller size. The one at the west end needs to be enlarged to lower the temperature at the west end so that the temperature inside the shed can remain consistent.

Don’t rush to ventilate after watering, because watering will lower the ground temperature in the shed. If you ventilate again at this time, the temperature in the shed will become even lower. If you want to increase the ground temperature It is more difficult, and roots are easily damaged when they grow in low-temperature soil for a long time, thus affecting growth and development. However, you cannot leave the shed without ventilation after watering, so that the moisture in the shed cannot be discharged. When the temperature drops at night, a lot of dew will be produced. In such a humid environment, vegetables are more likely to be infected with germs, and photosynthesis will be difficult. It will become worse, resulting in a decrease in the stress resistance of vegetables. After watering, open the shed in the morning on a sunny day, but keep the vents closed. When the temperature rises above 30 degrees, you can ventilate for half an hour. After half an hour, open a small opening for ventilation. When the temperature inside the shed drops to 23-25 ??degrees, you can open the shed. Close the vents.

When encountering continuous rainy weather, many growers choose not to ventilate in order to maintain heat. However, this will cause the humidity in the shed to be too high and cause various diseases. Growers should ventilate the shed to discharge moisture and harmful gases when the temperature permits. Ventilation should not be carried out too early on cloudy days to prevent the temperature in the shed from lowering. It is best to do it between 12 and 14 o'clock. The air outlet can be opened 6-8 cm and closed in time after about 10-15 minutes. After half an hour, let the air flow for another 10-15 minutes. Doing this two or three times in a row can drain out the moisture and harmful gases in the shed without any impact on the growth of vegetables.

In addition, growers can also set up a buffer film under the air vent to prevent weeds and dust outside the shed from entering the shed. It can also prevent cold air from blowing directly to the vegetables under the air vent, causing Vegetables have dry edges and broken skins. After the buffer film is installed, the cold air in the shed will be blocked on the back wall first, allowing time for convection between the cold air and the hot air in the shed. At the same time, the entrance of the greenhouse can also be said to be a large vent. When people enter the greenhouse, cold wind will enter, causing the vegetables at the entrance to be low and even cause cold damage. Therefore, growers can open a door on the back wall or both sides. , or open a small door at the entrance. Precautions for ventilation of greenhouses in winter

Because the temperature in winter is relatively low, the temperature inside the greenhouse must be paid attention to when ventilating. If the temperature in the shed is high and exceeds the temperature range suitable for vegetables to grow, ventilation can be carried out. However, you should pay attention to the time when ventilating, and always observe the temperature in the shed. If the time is too long, the temperature in the shed will be too low, causing freezing damage to the vegetables and affecting the normal growth of vegetables. Different vegetables require different temperatures at each growth stage. Growers must know clearly to prevent the temperature from being too low during ventilation.

During the ventilation process, do not let cold wind blow directly on the vegetables, which will cause the temperature of the vegetables to grow high and low. If they grow in such an environment, the vegetables will easily suffer from freezing damage, leading to poor growth.

In order to avoid temperature imbalance in the shed, growers should adopt the principle of ventilating from large to small and from small to large. The specific amount of air ventilation should be determined according to the temperature in the shed. High-temperature places should be ventilated early, while low-temperature places should be ventilated early. The place needs to be ventilated late so that the vegetables in the shed can be kept growing at the same temperature.

There is another very important point in ventilation in winter, and that is time. Do not ventilate too early, otherwise the temperature in the shed will drop significantly. If you suddenly encounter the invasion of cold air, the vegetables will definitely not be able to survive. Appropriate and therefore produce many diseases. The ventilation time should be chosen in the morning on a sunny day. Before ventilating, the shed should be ventilated to discharge harmful gases in the shed and allow the vegetables to better perform photosynthesis. If the ventilation is too early, the concentration of carbon dioxide will be reduced, which will affect the greenhouse effect. It is also detrimental to the growth of vegetables.

When growing vegetables in a greenhouse in winter, ventilation is essential. It can effectively adjust the temperature in the greenhouse. However, different vegetables have different temperature requirements. Only by keeping the vegetables at Only within the most suitable temperature range can you survive the winter safely. Moreover, the environment of the greenhouse is closed. If it is not ventilated for a long time, the air quality will be particularly poor, and some harmful gases will be produced, which is also detrimental to the growth of vegetables. Therefore, good ventilation can discharge the harmful gases in the greenhouse and improve the quality of the greenhouse. The air quality in the shed allows vegetables to grow better.

It can be seen from this that ventilation is particularly critical when growing in greenhouses in winter, and related precautions are also very important. However, many people do not pay attention to ventilation and feel that ventilation will easily cause vegetables to suffer from freezing damage. As long as Scientific and reasonable ventilation can achieve the best effect of ventilation and provide the most favorable growth environment for vegetables. Therefore, growers should be aware of the importance of greenhouse ventilation in winter and understand the relevant methods and precautions to avoid If any problem occurs, your own interests will be damaged. Only by allowing vegetables to grow in a good environment can the yield be guaranteed.