What factors should be noted when fertilizing in greenhouses?

First, farmyard manure must be thoroughly decomposed. Undecomposed farmyard manure contains pathogens and insect eggs, which can spread diseases. In addition, if farmyard manure is decomposed inside the greenhouse, it will produce ammonia gas that burns the vegetable seedlings.

Second, the fertilization method should be scientific and reasonable, and never applied blindly. After topdressing, cover with soil and water promptly, and never scatter fertilizer directly on the ground or on the plants, so as to avoid fertilizer volatilization or burning the vegetable seedlings. The amount of chemical fertilizer applied should be appropriate; excessive application of chemical fertilizer easily increases the salt concentration in the soil and affects the normal growth of vegetables.

Third, micronutrient fertilizers should be applied in appropriate amounts. Although the demand for micronutrient fertilizers by vegetables is small, their role in vegetable metabolism is very large. Micronutrient fertilizers are mostly applied as base fertilizer, and the amount must be accurate to avoid fertilizer damage.

Fourth, under drought conditions, vegetables in greenhouses should be fertilized with caution. Fertilizing when water is insufficient not only prevents the fertilizer effect from being fully exerted, but also causes the soil solution concentration to rise sharply, which easily burns the roots of vegetables.