High temperature in summer, shed vegetable management needs to do these three points!

With the arrival of hot summer, high temperature, glare, storm and other factors have a greater impact on the growth of facility vegetables. At this time, the winter and Spring or early spring vegetables will enter the middle and late growth stages, and the summer vegetables will enter the early stage of planting. According to the change of temperature, corresponding management measures are taken to ensure the normal growth of greenhouse vegetables, which is the key to cultivation.

1. Strengthen ventilation and regulate temperature

Due to the strong sealing property of plastic film in greenhouse vegetables, the moisture in the shed volatilizes slowly. If the humidity in the shed is too large, it will easily aggravate the occurrence of diseases. Therefore, attention should be paid to strengthening ventilation and ventilation, strengthening ventilation, adjusting temperature, promoting gas exchange between the shed and the outside of the shed, and effectively reducing the relative humidity of the air in the shed. Generally, the relative humidity of the air in the shed is maintained at 70%-80%.

Ventilation should be carried out step by step.

When the temperature in the shed is high, it is necessary to strengthen the ventilation and cool down, keep the wind and the mouth open, and control the plant growth, and enhance the heat resistance of the plant. Increase the amount of air release, open the bottom vents of the shed and the vents of the shed, and form an convective convection to dissipate the heat. It is best to set a windward film height of 60-80cm inside the shed when the wind is vented in front of the shed. The lower side is buried with soil, and the upper side and the greenhouse film leave a loophole of 10-15cm wide. When the front side of the greenhouse film is ventilated, the wind is blown from the upper side of the windward film, which has a good cooling result without causing the crop to be subjected to strong winds. Impact. When it rains, cover the vent film to prevent rainwater from entering the shed directly. After the rain, open the vents and ventilate.

➤ Illumination is a key factor in determining the temperature in the shed, so adjusting the illumination and regulating the room temperature are consistent.

When the temperature in the shed exceeds 35 ° C and lasts for more than 2 hours, the flower bud differentiation of the vegetables will be hindered, resulting in poor flowering and fruit setting, falling flowers and fruit. In the case of high temperature and strong light on sunny days, when the temperature in the shed cannot be controlled within the requirements of suitable vegetable growth by the method of air release, it is better for the vegetable farmer to adopt a shade net to cool down the heat-resistant varieties. When choosing a shading net, please also pay attention to it. We should choose the shading rate of about 60%, because this kind of shading net can play the role of shading and cooling, prevent the sunburning fruit, and let some light shine into the interior of the greenhouse. For example, tomatoes, cowpeas, leeks, celery and other crops, 60% shading nets are allowed to cool down. Not only can it control the temperature, but it also prevents the sunburn of the fruit.

喷雾 spray at noon to cool down.

At noon in summer, because the temperature in the shed is high, the evaporation of the leaves is large, and the water absorbed by the roots cannot meet the needs of vegetable transpiration. The vegetable farmers can install the micro-sprinkler spray in the shed to reduce the temperature of the shed.

2, reasonable watering, scientific fertilization

➤ Pay attention to the management of fertilizer and water in the late spring vegetables.

First, the summer temperature is high, and it should be watered in time. In the later stage of vegetable growth, high-nitrogen and high-potassium fertilizers can be applied with water to promote the growth of plants and fruits, and the effect of fully soluble fertilizer can be applied. The second is the foliar application of foliar fertilizer containing trace elements such as boron and calcium, which can play a role in maintaining flowers and fruits to a certain extent. According to the different growth stages of each vegetable and different growth characteristics combined with watering. Coordinating the relationship between watering and controlling the relative humidity in the shed, not only to ensure the normal demand of water for vegetables and to maintain a suitable soil temperature, but also to minimize the air humidity in the shed. The greenhouse should be poured once every 3-5 days. The amount of water should not be too large. The water should be poured in small water. It is best to use interlaced or ridged water, so that the water is poured, but the amount of water is not enough to meet the crop. Growing, and the temperature inside the shed is low. In the summer, the rainwater will pay more attention to the dredging of the ditch, and the water in the field can be discharged in time. Under-film dark or drip irrigation is recommended.

When watering, you should focus on three points:

First, pay attention to the watering time. Watering should be prohibited before the sunrise or after sunset. When the temperature is high, the water should be poured in time. The purpose of lowering the temperature, but not to accumulate water in the field; the third is to pay attention to strengthen the post-irrigation management, timely ventilation and drainage after irrigation.

Adhere to scientific formula fertilization, according to the characteristics of fertilizer required for each vegetable in different growth stages, combined with watering and reasonable topdressing. The tendency of heavy nitrogen fertilizer and light phosphorus and potassium fertilizer in the past was completely changed; in general, nitrogen fertilizer was the main stage, and potassium fertilizer was the main stage. Adhere to the organic fertilizer, supplemented by inorganic fertilizer (fertilizer), which can effectively reduce the occurrence of fertilizer damage, increase soil organic matter, improve soil, promote root development and increase vegetable yield.

3, do a good job of plant adjustment

Plant adjustment can improve the nutritional status of vegetables, improve ventilation and light transmission conditions, and increase vegetable yield and quality. Management measures mainly include hanging vines, pruning, topping, flower thinning, and fruit thinning.

➤ Note that the lower leaves of the plants should not be rushed to remove, which can play the role of shading and cooling, so that the ground temperature is relatively stable and not too high.

When vegetable products reach the maturity of the products, they should be harvested in time to ensure product quality, reduce nutrient consumption, and increase production per unit area.