How to use irrigating fertilizer for greenhouse vegetables?

How to use irrigating fertilizer for greenhouse vegetables? Please give guidance in greenhouse vegetable production, many farmers apply fertilizer too frequently, which often causes soil consolidation, rotten roots, retting roots, plant wilting and other phenomena, seriously affecting the economic benefits of farmers. For this reason, it is suggested that "four combinations" of fertilization should be achieved in greenhouse vegetable production. (1) High quality fertilizer shall be selected with the combination of topdressing and flushing fertilization. Based on multi-component compound fertilizer, the combination of topdressing and flushing application is adopted to solve the problem of fertilizer demand for surface roots on the one hand, and topdressing can activate the soil layer, increase the root system and alleviate the fertilizer effect on the other hand. (2) the combination of organic and inorganic fertilizers are mainly used by many farmers, whether they are applied or topdressing. Although some irrigation fertilizers contain humic acid, most of the inorganic fertilizers are ammonium nitrate, urea and other nitrogen fertilizers, which grow fast in the short term, have large leaves and long stems, and grow well on the surface, but lack of long-term effect. Attention should be paid to the balance between vegetative growth and reproductive growth, and some fertilizers include cake fertilizer (sesame seed cake, cotton cake, bean cake) and diammonium phosphate (or ammonium nitrate), and other fertilizers such as potassium chloride and potassium sulfate. The reason is that it takes a certain time for cake fertilizer to ferment. (3) the combination of biological fertilizer and chemical fertilizer contains more than ten kinds of beneficial bacteria, which can activate soil and regulate nutrients. Combined application with inorganic fertilizer (chemical fertilizer) can relieve fertilizer damage, increase soil organic matter and promote root development. (4) the combination of big water and small water application, many farmers carry fertilizer with big water in both seedling stage and fruiting stage, resulting in excessive fertilizer and water, causing seedling disease, root rot and root retting. No matter biological fertilizer, organic fertilizer and chemical fertilizer, it depends on the rational amount of fertilizer used by seedlings. "small fertilizer and water to raise roots, medium fertilizer and water to protect seedlings, and large fertilizer and water to raise fruit" is this truth. The effect of ploughing and loosening soil in time after fertilizer and water is better. Get more water-soluble fertilizer application technology