Pay attention to "seven don't" and don't apply undecomposed cake fertilizer when fertilizing greenhouse vegetables. Because the cake fertilizer carbon and nitrogen ratio is small, fast decomposition, local easy to produce high temperature and high concentration of ammonia and organic acids, easy to burn roots. The cake fertilizer should be broken up, soaked in human excrement and urine for about 3 weeks, and then applied after high-temperature fermentation.

Do not apply ammonium sulfate and ammonium bicarbonate. Ammonium sulfate is a physiological acid fertilizer, which will increase the acidity of the soil and destroy the soil structure after application. After the application of ammonium bicarbonate, a large amount of ammonia is volatilized, which is not good for the growth of vegetables.

Do not apply fertilizers containing chlorine. Chloride ions can reduce the starch and sugar content of vegetables, make the quality of vegetables worse, reduce the yield, and chloride ions remain in the soil, can lead to soil acidification, easy to cause soil decalcification.

Do not fertilize under drought conditions. Vegetables are water-happy crops. When the soil is dry, fertilization will not only fail to give full play to the fertilizer effect, but also increase the concentration of soil solution suddenly, which is easy to burn the roots of vegetables. Vegetable fertilization should be combined with irrigation, ditching and fertilization should be carried out, and irrigation should be carried out after the fertilizer is buried tightly, or top dressing should be carried out according to the water.

Do not overapply diammonium phosphate. Vegetables need a lot of nitrogen and potassium, and less phosphorus. Even if phosphate fertilizer is applied, diammonium phosphate should not be mixed with alkaline fertilizers such as plant ash, so as not to cause ammonia volatilization and cause ammonia harm.

Do not topdressing potassium fertilizer in the late growth period. Vegetables generally need more potassium fertilizer before and after flowering, and then gradually decrease. And phosphorus is easily absorbed and solidified by the soil, losing fertilizer efficiency. Therefore, phosphate fertilizer is suitable as a base fertilizer or concentrated in the soil layer with dense roots in the early stage of vegetables.

Do not apply iron fertilizer and rare earth fertilizer into the soil. Iron ions are easily fixed by the soil into insoluble compounds and lose fertilizer efficiency, so iron fertilizer should not be applied to the soil. Iron is not easy to flow on the leaves, should be used foliar spraying, can use 0.1~0.3 ferrous sulfate solution evenly sprayed on the vegetable leaf surface, or with 0.05~0.07 rare earth fertilizer solution in the vegetable leaf surface spraying, spraying 50~60kg solution per mu.