Characteristics of foliar fertilization：
(1) Foliar fertilization is not affected by soil factors, and fertilizer utilization is high.
Since the nutrient is sprayed directly onto the leaf surface, it does not need to pass through the soil, avoiding the nutrients (such as Fe, Mn, P, Zn, Cu, Mo, etc.) faced by traditional fertilization being adsorbed and fixed by the soil, and the anti-knot between different elements. The problem of nutrient loss and decomposition loss is high, so the fertilizer utilization rate is high. Foliar fertilizer is applied directly to the surface of plants, with large contact area and many absorption points. According to statistics, about 70% of the applied foliar fertilizer adheres to the surface of the leaves, 30% falls on the ground, and about 80% of the leaves attached to the leaves are absorbed by the leaves, so about 60% of the total application. It is absorbed and utilized. Foliar fertilization compared with soil fertilization, the amount used for foliar fertilization is only 1/10--1/5 of soil fertilization. Therefore, foliar fertilizer has the advantage of saving fertilizer, and avoids nutrients being soiled in the soil. Fixed and leached.
(2) Foliar fertilization can quickly supplement the nutrients needed during crop growth.
For example, it takes 4-5 days for urea to be applied to the soil to be effective, and foliar application for 1-2 days can have obvious effects. Spray 2% concentration of superphosphate extract to transfer to all parts of the plant in 5 minutes. When the crop presents some symptoms of deficiency, the foliar fertilizer containing the element is sprayed, and the corresponding symptoms of deficiency can be quickly improved.
(3) Foliar fertilization can enhance the metabolic function of plants and promote the absorption of nutrients by roots.
Mainly in the significant increase in photosynthesis intensity and greatly improve the activity of the enzyme. When foliar fertilizer is applied to garlic, the activity of enzymes in roots, stems and leaves is increased by 15%-31%. When the roots are weak in the early growth stage and in the late stage, foliar fertilization can timely supplement the plants and improve the quality and yield of the products.
(4) Meet the special needs of fertilizer.
Foliar fertilization is carried out to solve a physiological nutritional problem of a crop and a special need for a certain fertilizer. If the magnesium deficiency of the grape can cause the stem to wither and the fruit to fall, only the spraying of magnesium on the leaf surface is effective.
(5) Foliar fertilization can avoid groundwater pollution caused by large amount of fertilization and leaching in soil.
(6) Some foliar fertilizers can be combined with pesticides to reduce labor costs.