There are two main considerations for using shade nets:
First, choose according to the plant species. Some plants require high light intensity, while others require less. For example, tomatoes are a plant that requires relatively high light. Currently, shade nets on the market are generally divided into two types: black and silver-gray. These two types of shade nets have different light transmittance. Black shade nets have a high shading rate and a relatively good cooling effect, suitable for short-term use during the hottest periods of summer. Silver-gray shade nets have a refractive index of around 45%, which can meet the growth needs of light-loving plants while providing shade.
Second, use according to the duration of shading. The use of shade nets should take into account the timing of shading. For example, when the temperature is low in the morning and evening, shade nets can be omitted, and only used during the midday when the temperature is higher. They can also be omitted on cloudy or rainy days because there is no sunlight. Additionally, when covering the greenhouse, try not to place the shade nets too close to the greenhouse surface to prevent the heat absorbed by the nets from entering the greenhouse through the film. Spray Cooling Equipment
Spray cooling equipment has the advantages of good cooling effect and low operating cost. Its principle is that water is added to high-pressure micro-mist nozzles to generate ultra-fine water mist. This water mist, upon contact with the air, quickly absorbs heat from the air and evaporates, continuously lowering the ambient temperature and achieving a cooling effect. In addition, using spray cooling equipment in greenhouses can maintain air humidity, preserve plant water content, and promote growth.
Covering Method
The plastic film used in greenhouses will become old and damaged after a period of use. Many cultivation practices involve covering new greenhouses with the old film as a cooling method. While the old plastic film has reduced light transmittance and can block some sunlight, it cannot completely block sunlight. Covering with more film only reduces the greenhouse's ventilation efficiency and does not achieve an effective cooling effect. Furthermore, if the film is not covered tightly, it can easily be blown away by the wind.
