The common green house ventilation management

Ventilation management of greenhouse in spring
1、 The size of air outlet varies with different camber(green house）
The size of the air outlet in spring can not be completely defined by a certain data, because the structure of the greenhouse is different, and the cooling time and speed are also different. For the shed with large camber, because the camber of the shed surface is appropriate, the hot air flow is easy to be discharged along the upper part of the shed film. Even if the vent is small, a better ventilation effect can be achieved. For the low old shed with long planting years, because the arch of the shed is small and the shed surface is flat, the hot air flow in the shed is discharged slowly from the vent and the temperature in the shed is high. Under normal circumstances, such a greenhouse will open the top vent to 40 cm wide, which is the same as that of a greenhouse with high height and large camber to 30 cm.

2、 Pay more attention to sub ventilation in spring（green house)
After opening the shed for one hour in the morning, open the upper air outlet for about 3-5cm and let down the wind. The purpose is to discharge the moisture in the shed and supplement the carbon dioxide in the shed, so as to supplement the raw materials for the smooth progress of photosynthesis. When the shed temperature rises above 28 ℃, gradually open the vent and keep the temperature in the shed no more than 33 ℃ (for warm vegetables such as cucumber and towel gourd).

3、 It is windy in spring. Pay attention to wind prevention at the vent(green house)
Increase the density of the vent rope, and it is better to use a wide cloth strip with large friction. When this cloth strip is used to tie the loose knot and fix the shed film, the friction is large, and the loose knot is not easy to be blown loose by the strong wind. Many vegetable farmers plan to use nylon rope as wind rope conveniently. Because the friction is small, vegetable farmers should appropriately increase the density of nylon wind rope and fix it to prevent the air outlet from being blown by the wind. At the same time, vegetable farmers should also pay attention to check at any time in windy weather to prevent the ventilation rope from loosening and the air outlet from closing.