In the technical aspects of greenhouse vegetable planting, fertilizer damage and high temperature damage are important factors that affect the yield, quality and benefit of vegetables. The following are the necessary prevention methods.
1. How to prevent fertilizer damage
① Apply fertilizer deeply. Chemical fertilizers should be applied deeply or dissolved in water.
②Appropriate fertilization. Due to the low loss of fertilizer in the greenhouse, its application rate should be lower than that of open-field vegetables.
③Applying organic fertilizers. In particular, manure and human and animal manure must be fully decomposed and fermented before application.
④ Ventilate at the right time. Ventilation should be strengthened after application, and a certain amount of ventilation should be maintained at night to prevent harmful gases from accumulating in the greenhouse when the fertilizer is decomposed and causing poison to vegetables.
⑤ Fertilization distance should be appropriate. Topdressing quick-acting fertilizers such as urea should not be close to the roots to prevent root burning. When applying leaf fertilizer, the appropriate concentration is 0.5%-1%.
⑥ The application amount should not be too large. Regardless of topdressing or foliar spraying of chemical fertilizers, the dosage must be appropriate.
2. How to prevent high temperature hazards
① Strengthen ventilation. Adjust the air in the greenhouse to make the air fresh and eliminate all harmful gases in the greenhouse. When the outside air temperature rises to about 18°C, ventilation is gradually carried out.
②Control the appropriate temperature. The temperature in the greenhouse is maintained at 20-25℃ during the day and 15-18℃ at night. The temperature control can be combined with measures such as ventilation and water spraying.
③Replenish water in time. When the soil in the greenhouse is short of water, water should be added in time, and the temperature should be adjusted with water to reduce high temperature hazards.
