How to scientifically manage and cool greenhouse vegetables in high temperature weather at present?

Excessive temperature has a bad effect.

After a long summer, it is normal that the temperature in the shed reaches above 40 degrees during the day. In this way, because the temperature in the shed is too high, vegetables will grow poorly and there will be high temperature obstacles. For example, the phenomenon of falling flowers and fruits is serious, sun-dried fruits and deformed fruits increase, grow too fast, and premature aging. , seriously reducing the planting benefit. Therefore, how to quickly and effectively reduce the temperature in the greenhouse in summer is a concern of all fruit and vegetable growers.

Auxiliary measures, internal and external collocation

Talking about cooling can be considered from two aspects, the first is outside the shed and the second is inside the shed.

Outside the shed: mainly by covering various awnings on the shed film, the incidence of light is reduced, and the light intensity in the shed is reduced to achieve the purpose of shading and cooling.

In the shed: through supporting measures, reduce the storage of heat and achieve the purpose of cooling.

Conventional method, for reference only

Method 1: sunshade net

At present, there are two kinds of sunshade nets, white and black, both of which have their own advantages and disadvantages. On the cooling effect, black sunshade net is better than white; But in terms of saving time and effort, white is simpler, because black umbrellas need to be pulled every day, which is time-consuming and laborious.

The best way to install the sunshade net is to support the sunshade net and leave a gap of about 20 cm with the shed film, so that the sunshade and cooling effect will be better after the ventilation belt is formed.

Method 2: Mud splashing

Mud splashing is an indigenous method, although it is not as effective as sunshade net, it can also reduce the temperature in the shed. According to the light intensity, we can flexibly master the concentration and dosage of mud, but the disadvantage is that the anti-erosion effect is poor.

Method 3: Spray coolant.

Greenhouse cooling agent has attracted more and more attention and application at present, and the effect is very obvious. I suggest that fruit and vegetable growers and shed friends can try to compare and try the effect. Bright brand is a brand, so try it.

Method 4: spray water in the shed to cool down.

Some people describe it as a vegetable greenhouse with air conditioning. The specific method is to install micro-spraying equipment (spraying) above the hanging rope. Two or three pipes are laid in the greenhouse, one end of which is connected with a water pump. When the temperature is high, it can be sprayed for 20-30 minutes to achieve the purpose of cooling down, and it can be done frequently with good results. This will not affect the light, but attention should be paid to controlling the humidity in the shed to prevent diseases.

Method 5: Strengthen the management of shed reform.

Ventilation in the shed: pay attention to air circulation, otherwise the effect will be poor.

Watering: Don't water in the high temperature period at noon, which will easily lead to capillary root damage and even plant wilting and death in severe cases.

Thinning branches and beating leaves: the requirements should not be too harsh, and leaves should be properly kept out of the light.

Cooling is the measure, and raising roots is the key.

Whether using sunshade net or spraying coolant, or installing air conditioner in the shed, these are all supporting measures for high temperature obstacles.

High temperature has the greatest influence on vegetables because of the strong transpiration of leaves. If the root system is not developed enough, the water absorbed by the root system from the soil can not meet the needs of plant evaporation, and the nutrient supply is insufficient, which will cause the leaves of vegetable plants to curl and fall off, leading to an increase in deformed fruits, a decline in quality, and even premature aging and withering. In addition, high temperature leads to decreased crop resistance, hindered overall growth, and aggravated virus disease, powdery mildew and mite damage.

High temperature is easy to cause root damage.

The optimum ground temperature for root growth is 20-22 degrees. From June to July, even if the sunshade net is covered, the temperature in the shed will still reach 40 degrees or even 45 degrees. In this case, the ground temperature can reach more than 30 degrees, which is far beyond the suitable range of crop root growth. The direct consequence of root system injury is that the overall growth of crops is not good.

Therefore, in order to truly solve the problem of high temperature obstacle of protected vegetables in summer, the most fundamental and core measure is to cultivate developed roots and improve crop stress resistance.

There are many problems with high temperature, so be careful in everything.

First, prevent viruses and pests. High temperature season is the occurrence period of pests, especially thrips, mites and whiteflies. It is suggested to use a 60-200 mesh insect net to prevent pests from entering the shed.

Secondly, water and fertilizer should be timely. When the high temperature comes, water should be poured every 5-7 days. When watering, root products should be cultivated with water. Water-soluble fertilizer is recommended to be used several times.

Third, prevent rainwater from entering the shed. Rainwater entering the shed is easy to cause various diseases such as root rot. Therefore, while paying attention to ventilation and cooling, we should always pay attention to climate change.