What to Do If a Pear Tree Does Not Bear Fruit? A Detailed Guide to Practical Technical Measures
1. Avoid excessive application of nitrogen fertilizer. Some farmers grow sweet potatoes between their pear trees; they grow sweet potatoes to cut the vines to feed pigs, so they frequently pour pig manure, and the pear trees grow tall and large but bloom without bearing fruit. For this type of pear tree, nitrogen fertilizer application should be stopped and phosphorus and potassium fertilizers increased; apply potassium dihydrogen phosphate by trenching at the drip line of the canopy and by spraying the canopy.
2. Eliminate waterlogging in the orchard. Some pear trees are planted in fields where, although the soil layer is deep and the soil fertile and the pear trees grow well, drainage is poor. During the flowering period there is generally too much rain, and growth is checked by waterlogging, so that few fruits set or even none set at all. In this situation, drainage ditches should be opened properly so that irrigation is possible in drought and no waterlogging occurs on rainy days.
3. Prune and tie down branches appropriately. Some pear trees grow excessively vigorously; the main branches and some of the tree's scaffold branches should be cut away, and the densely growing branches should be pulled with ropes and tied down toward the edge of the canopy. This can both control excessive vegetative growth and increase the light-receiving area and light intensity, which favors fruiting.
4. Plant additional pollinator trees. Pears are cross-pollinated plants, and pollination within the same cultivar has a very low fruit-setting rate or even no fruit set. Planting additional pollinator cultivars can promote pollination and fruit set in pear trees; generally a ratio of pollinator trees to the original trees of 1:3 is more suitable.
5. Artificial supplementary pollination. Choose cultivars with strong compatibility and large pollen amounts as pollinator cultivars, collect anthers that are mature and about to split or have just split, place them in diffused light to dry with newspaper underneath, so that the anthers split, collect the pollen, and then carry out artificial pollination. Artificial pollination methods include hand pollination and liquid pollination. Hand pollination is carried out according to the number of fruits to be retained per inflorescence. When pollinating, put the pollen in a small bottle, dip a writing brush in the pollen, and lightly wipe it on the stigma of the flower; each dip of pollen can pollinate 10 flowers. Liquid pollination is made by mixing 25 ml of pollen with 10 kg of water, 1 kg of granulated sugar, and 10 g of boron fertilizer into a liquid pollen for spraying, and it is required to finish spraying within 2 hours after mixing.
6. Spray plant hormones. Spraying plant hormones during the flowering period can increase the fruit-setting rate; spraying plant hormones during the young fruit swelling stage can reduce fruit drop, promote fruit weight, improve quality, and increase yield.