Techniques of spraying foliar fertilizer on fruit trees

Spraying period and dosage 1, nitrogen fertilizer should be used in the early and late growth of fruit trees, properly combined with phosphorus and potassium fertilizer. Proper spraying concentration can effectively promote shoot growth, increase fruit yield and be beneficial to flower bud differentiation. The concentration of urea is 0.2-0.3% in the early stage and 0.3-0.5% in the later stage; the concentration of feces and urine of mature people is 0.5% in the early stage and 10% in the later stage. 2. Phosphate fertilizer spraying should grasp the principle of less in the early stage and more in the middle and later stage. The effect of ammonium phosphate is the best, the concentration is 0.5-1%, the concentration of potassium dihydrogen phosphate is 0.2-0.5%, and the concentration of superphosphate leaching solution is 1-3%. 3. Potash fertilizer is mostly used in the middle and later stage. It can effectively promote fruit coloring, improve fruit quality and enhance disease resistance. The concentration of potassium sulfate and potassium nitrate is 0.3-0.5%; plant ash is 5-15 kg plus 0.5 kg of water. After soaking for 24 hours, the residue can be filtered and sprayed. 4. The leaves of trace elements are green and yellowish white, and can be sprayed with 0.3-0.5% ferrous sulfate solution every half a month during the growing period. When it is found that the fruit is deformed and there are dry spots on the appearance, 0.3-0.5% borax solution can be sprayed before and after flowering in the following year. The best spraying time is in the semi-cloudy and windless day, which should be before 10:00 and after 4pm. Spraying nitrogen fertilizer at full flowering stage can increase fruit setting rate; spraying nitrogen fertilizer at young fruit stage can promote young fruit expansion; spraying nitrogen fertilizer combined with phosphorus fertilizer in May and June can effectively promote flower bud differentiation; spraying phosphorus and potassium fertilizer in the later stage can increase fruit sugar content and promote coloring; trace elements can be sprayed before and after flowering. Foliar spraying can be carried out alone, or mixed with several fertilizers or pesticides to save labor. However, mixed spraying should pay attention to that fertilizer or pesticide mixed application can not produce fertilizer or drug damage. Urea is a neutral fertilizer and can be mixed with a variety of pesticides. Pesticides and fertilizers with different acidity and basicity can not be mixed, such as all kinds of micro-fertilizers can not be mixed with plant ash, lime and other alkaline fertilizers; zinc fertilizer can not be mixed with calcium superphosphate. Before the mixed use of fertilizer and pesticide, put a small amount of fertilizer solution into the same container, if there is no turbidity, precipitation, bubbles and other phenomena, it shows that it can be mixed, otherwise it can not be mixed. Foliar fertilizer spraying should be first up and then down, uniform and thorough, mainly spraying the back of the leaf. Foliar fertilizer spraying is generally valid for only 12-15 days, requiring more than 2-3 consecutive times. Long-term spraying will affect root growth and weaken root physiological function, so foliar fertilizer spraying should be used as an auxiliary measure to rapidly replenish nutrition on the basis of soil fertilization.