The fertilization of apple trees should be based on base fertilizer. The best time for basal fertilizer application is autumn, early-maturing varieties can be carried out after fruit harvest; mid-late-maturing varieties can be carried out before fruit harvesting. Autumn is the period of rapid root growth of apple trees. The cut roots after fertilization are easy for wound healing, and they play a role in root pruning to promote the germination of new roots and facilitate the absorption and accumulation of nutrients.

In general, 2-3 kg of bio-organic fertilizer is applied to young trees and 5--8 kg to adult fruit trees. The application time of top dressing varies with tree vigor, generally before germination, flowering and fruit expansion. The fertilization method depends on the size of the tree. When the tree is small, use circular fertilization. The fertilization position should be 0.5-1.5 meters outside the canopy, with a trench of 20-40 cm wide and 20-30 cm deep. Apply 1-2 kilograms of biological organic fertilizer, mix the fertilizer with the soil and apply it into the ditch, and then fill the ditch. Adult fruit trees are fertilized in the whole garden, 100 kilograms of bio-organic fertilizer is applied per mu, and the fertilizer is turned into the soil in combination with field tillage. Short-branched apple trees are mostly densely planted, with good early fruit and high yield, and require more fertilizer than ordinary types. Generally, young trees use 200-300 kilograms of bio-organic fertilizer per mu per mu as base fertilizer, and adult short-branched apple trees use 400-500 kilograms of bio-organic fertilizer per mu per mu. Reapply autumn basal fertilizer and topdressing in time before flowering, fruit expansion, and flower bud differentiation. Spur apple trees are fertilized by furrow application, and the amount of each application should not be too large. When the application amount is large, the whole garden should be spread and moderately deep turned to prevent fertilizer damage.

The time and method of fertilizing pear trees are basically the same as those of apples. The basal fertilizer is applied in autumn, and the top dressing is applied before germination, flowering and fruit expansion. 1--2 year-old saplings, 200-300 kg of bio-organic fertilizer per mu is applied as base fertilizer. At the same time, 0.5--1 kg of ternary compound fertilizer is applied to the trees, and the top-dressing plant is applied with bio-organic fertilizer 2--3 each time kg. Adult tree basal fertilizer is generally applied with 300-500 kg of bio-organic fertilizer per mu, plus 1-1.5 kg of ternary compound fertilizer for plants, and 3--5 kg of bio-organic fertilizer for topdressing plants, applied in strip furrow or radial furrow.