How to apply fertilizer in apple orchard during the peak fruit period of growing apple

1. Base fertilizer

The optimum period of basal fertilizer application is from the middle of September to the middle of October, and organic fertilizer should be mainly applied. The amount of organic fertilizer applied per mu should reach 3000-4000 kg, calculated according to the yield of 2000-3000 kg per mu in full fruit stage. At the same time, appropriate amount of quick-acting chemical fertilizer should be applied, and pure nitrogen 6-10 kg, P2O5 6-14 kg and K20 2-4 kg should be applied per mu.

2. Topdressing

(1) Fertilization before germination (mid-late March). N 8- 15kg, P 2O 5 2- 5kg, K 20 8- 15kg per mu. Function: Provide nutrition for budding, flowering, young fruit development and new tip growth. (2) Fruit setting fertilizer (early maturity varieties applied in late May, late maturity varieties applied in mid-June). N 6-10 kg, P 2O 5 2-5 kg, K 20 8-15 kg per mu. Function: Enhance leaf function, promote flower bud differentiation, enlarge fruit, improve fruit quality. (3) The second fruit expansion fertilizer of late-maturing varieties (applied in the middle of August), k20 3-4 kg per mu, a small amount of phosphorus fertilizer, nitrogen fertilizer is generally not applied (tree potential is weak, appropriate topdressing).

3, foliar fertilizer

(1) before germination. Spray 1%-5% urea 2-3 times. (2) After germination to before mid-July. Spray once every 7 days, according to the proportion of urea twice and potassium dihydrogen phosphate once, the concentration is 0.3%-0.5%; after the middle of July, the leaves will fall. Spraying according to the proportion of potassium dihydrogen phosphate twice and urea once, the concentration is 0.3%-0.5%. (3) Before flowering. Spray borax with concentration of 0.3%-0.5% for 2-3 times. (4) before bagging fruit. Spray 0.2%-0.4% calcium nitrate 3 times. (5) deficiency. For the corresponding prevention and control, iron deficiency spray 0.3%-0.5% iron fulvate; zinc deficiency spray 0.3%-0.5% zinc sulfate; calcium deficiency spray 0.3%-0.5% amino acid calcium.