Vegetable shed ventilation

The purpose of ventilating and ventilating greenhouses is to adjust the temperature, humidity, and carbon dioxide concentration in the shed and to discharge harmful gases. It is particularly important to properly and properly grasp the ventilation and ventilation techniques. I have been engaged in vegetable greenhouse production and technical guidance for many years and found that even farmers who have been engaged in vegetable production for many years often make mistakes in ventilation and ventilation skills in greenhouses, causing unnecessary losses in production. In the winter and spring season, how can the sheds for growing vegetables be ventilated?

In the actual production and operation process, the following principles and measures should be noted.

1. Temperature. When the greenhouse is ventilated, the temperature in the greenhouse must be higher than the temperature suitable for the growth of the specific vegetable, so as to avoid cold or freezing damage to the vegetables caused by the low indoor temperature after the ventilation. Therefore, we must understand and grasp the temperature requirements of various stages of growth and development of various vegetables.

2. The amount of air release. When the greenhouse is ventilated, it must adhere to the principles of small to large, small to large, and windy. At the same time, we must pay attention to adjust the local temperature difference in the shed, relatively early ventilation in high temperature, put a larger tuyere; When the air outlet is closed, it should be gradually reduced from large to small, and gradually. In addition, when ventilating and ventilating, cold air should be prevented from blowing directly into vegetable plants in the shed, causing the temperature to fluctuate, causing frozen damage to the leaves and young fruits of the vegetables.

3. Ventilation time. The purpose of ventilating and ventilating is to eliminate humidity and cool down, to meet the demand of carbon dioxide for photosynthesis of vegetables in greenhouses. Therefore, ventilation and ventilation time should generally be performed when the temperature inside the greenhouse is too high, the relative humidity is relatively high, and the photosynthesis is accelerated. Generally, it takes 1 to 2 hours after the curtain is opened on a sunny day. In addition, after the application of watering fertilizer or spraying pesticides, due to increased humidity, ventilation should also be short-term. In cloudy snow weather, when the indoor relative humidity is high, carbon dioxide is deficient, and harmful gases are accumulated, a small amount of wind should be released for a short period of time to meet the demand for carbon dioxide from vegetables and reduce nutrient consumption in plants. Improve plant resistance to cold. In the event of a long period of overcasting, it is necessary to expose the covers outside the shed, and the amount of air to be blown off is small to prevent the light from becoming excessively strong and the transpiration will intensify, causing the vegetables to lose water and wilt.

PCR Reagent For Vetor-borne Diseases

PCR,PCR Reagent,Molecular diagnosis,Vetor-borne Diseases

Shenzhen Uni-medica Technology Co.,Ltd , https://www.unimed-global.com