Most nursery-produced fruit trees have tops that are one to two years old. The length of time required for them to bear fruit after planting varies with the kind of fruit. Apples usually bear fruit in 4-7 years while plums may bear as early as the third season after planting. All fruit trees require pollination to produce fruit. Unless pollination takes place, trees can blossom abundantly but not bear.
Bees are necessary for cross-pollination between two different tree fruit varieties.
High winds, steady rainfall or cold temperatures can reduce bee movement during the flowering period. Consequently, poor pollination may occur under adverse weather conditions, resulting in poor fruit set. Extremely low temperatures during winter dormancy may kill or damage fruit buds. In addition, spring frosts during the flowering period may also drastically reduce fruit set. Fruit trees that are grown near large shade trees are often poor producers.