Three details most easily overlooked in greenhouse management
Detail one: Ventilation should be carried out in stages
On sunny days, ventilation should be carried out 1 hour after the straw mats are uncovered. When ventilating, first open a small gap, and as the temperature inside the greenhouse rises, gradually widen the vent, so as to facilitate the entry of carbon dioxide from outside the greenhouse and promote the photosynthesis of vegetables. In the afternoon, do not close the vent all at once either; close it gradually. You can first close half of the vent, and after 30 minutes close the vent completely. Alternatively, first close the vent, then open it again to ventilate and cool for 10**15 minutes, repeat this twice, and when the temperature inside the greenhouse stabilizes at around 15°C, the vent can be closed completely.
If there is continuous cloudy weather and the outside temperature is relatively low, the greenhouse should focus on heat preservation, but it should not be left unventilated for this reason. If it is not ventilated, the humidity inside the greenhouse will be too high, which will provide conditions for the infection and spread of diseases.
Ventilation should be carried out between 12 noon and 2 pm, opening the vent to a width of 10 cm is sufficient, ventilating for 10**15 minutes each time, once every 20**30 minutes, and ventilating 2**3 times in succession can achieve a very good humidity-reducing effect.
Detail two: Supplementary lighting is essential
After entering winter, insufficient light becomes an important reason affecting the increase of vegetable yield. Most vegetable growers know that installing reflective film inside the greenhouse is beneficial to vegetable growth. However, some vegetable growers hang the reflective film too low, and the vegetable plants easily block the light, resulting in a poor effect from the reflective film. When hanging the reflective film, a reflective film 1**1.2 m wide should be hung at a height of 1.7 m on the back wall. The entire back wall of the greenhouse should not be covered with reflective film, to prevent reducing the heat storage capacity of the back wall. For vegetables such as cucumbers and loofahs that require stronger light, special supplementary lights can be installed in the greenhouse, supplementing light for 2**3 hours, extending the light exposure time of the vegetables, so as to promote the accumulation of organic matter in the vegetables and increase yield.
Detail three: Hang a hygrometer inside the greenhouse
Controlling humidity is one of the key points in winter greenhouse vegetable management. Nowadays, many vegetable growers know that a humidity of 70%**80% inside the greenhouse is relatively suitable. But because many greenhouses do not have a hygrometer hanging inside, vegetable growers cannot accurately grasp the humidity inside the greenhouse, leading to frequent diseases. Therefore, a hygrometer should be hung inside the greenhouse, and this point is especially important for vegetable-growing beginners. When the humidity inside the greenhouse is too high, in addition to ventilating to reduce humidity, vegetable growers can also spread plant ash on the ground to reduce humidity.