How do greenhouse vegetables cope with the arrival of cold air?

In early winter, the weather changes greatly, after the maintenance of thermal insulation facilities, but also pay attention to flexible thermal insulation according to weather changes. Temperature management should take balanced heat preservation as the main line. After the temperature decreases, the front air vent should be closed in time, and the insulation cover should be covered to ensure that the night temperature in the shed is not lower than 12 ° C, and it is not possible to over-heat. The low temperature conditions for a short time are good for vegetables to adjust their own functions and improve their stress resistance.

Reduce humidity, reduce disease

In winter, the main reason for the disease is high humidity. If the humidity can be controlled within the appropriate range, it can greatly reduce the occurrence of diseases and ensure the yield and quality of vegetables.

Methods to reduce humidity:

Cover the operating line with organic matter to reduce water evaporation

In the operation line, cover some organic matter with good permeability and hygroscopic effect, such as rice husk, cover the thickness of 3-4 cm. After the operation of covering the rice husk, it can not only reduce evaporation, but also play a moisture absorption role, and its good permeability after laying, will not lead to soil compaction, change the rice husk into the soil, can improve the soil, increase the soil permeability, decomposition can also improve the soil fertility. Covering crushed corn and wheat straw, the hygroscopic effect is better than that of rice husk, and these crop stalks can also release more heat and carbon dioxide in the process of decay, increasing the temperature in the shed and the photosynthesis of vegetables. Conditional vegetable farmers can also lay turf, turf has odorless, soft texture, water absorption and good water retention, rich in organic matter and humic acid and other characteristics. The hygroscopic effect of laying grass charcoal in the operation line is better than that of rice husk and straw. It is also a good organic fertilizer for use in soil.

Planting row mulch arch

One of the purposes of mulching is to reduce the evaporation of water into the air, if the mulching film is covered with ground, water will easily be stored on the mulching film when watering, which can not reduce the effect of evaporation. Therefore, it is best to arch the mulch film, and carry out dark irrigation under the film when watering, which can reduce water evaporation and have a good effect on improving the ground temperature.

Increase the temperature + let out the wind, accelerate the dispersion of humidity

When the temperature in the shed is high, the relative humidity is naturally small. At the same time, the rise in the temperature in the shed can speed up the gas exchange with the outside world, and exhaust the moisture to the outside of the shed to achieve the purpose of reducing humidity. In winter, increasing the light in the shed is the most critical measure to improve the temperature. Farmers can improve the light and temperature by wiping the shed film, increasing the transmittance of the shed film, and hanging reflective curtains or fill lights. Ventilation moisture, to grasp the ventilation time. After pulling up the covering in the morning, do not hurry to let out the air, the shed is closed for half an hour to an hour, after the temperature in the shed has increased, you can pass a small wind to exhaust the humidity, close the vent for half an hour to continue to raise the temperature, without affecting the growth of vegetables, as far as possible to increase the temperature, and then pull the big vent ventilation. In the afternoon, when the temperature drops to about 25℃, close the air vent. During the period from closing the air vent to placing the covering, the humidity in the shed will increase. It is recommended to ventilation for 10-15 minutes half an hour before placing the covering, which can effectively reduce the humidity in the shed at night.

Nourish the roots and protect the leaves, and enhance the resistance to disease

In the farming operation of low temperature season, improper watering and fertilization is easy to damage the root system. When watering, the groundwater water temperature should be selected when it is close to the ground temperature, so as to prevent the large temperature difference from causing the root explosion.

Improper fertilization in low temperature season is easy to damage the root system, the general chemical fertilizer will absorb heat when dissolved, resulting in lower water temperature, so the chemical fertilizer should be equipped with mother liquor in advance, after soaking for a period of time.

In the production, attention should be paid to the use of functional fertilizers such as humic acids, amino acids, alginic acids, chitin, nucleotides and other fertilizers and biological fertilizer, which can stimulate plant roots and improve the resistance of plants.

In low temperature season, the root system of most vegetables is weak in water absorption and fertilizer absorption, and is easy to show the symptoms of leaf yellowing or even deficiency. It is suggested that vegetable farmers can directly spray amino acid leaf fertilizer combined with medium and trace element leaf fertilizer on the leaf surface to extend the functional period of leaves, prevent premature leaf aging, and make each leaf provide and accumulate the most dry matter, increasing yield.