Cross-pollination refers to plants that require pollination from other plants, as opposed to self-pollination. Many fruit trees can cross-pollinate as well as self-pollinate, but there are some fruit trees that cannot pollinate without the aid of another fruit tree. Although cross-pollination isn't mandatory for bearing fruits in some trees, it can help in producing more fruits on each tree. Knowing which fruit trees rely on cross pollination, and which do not, can make it easier to produce a bountiful harvest of fruit every harvest.
Apple trees cannot pollinate on their own, and they require the pollination from trees of the exact type. For example, an apple tree producing Granny Smith apples cannot cross-pollinate to an apple tree that produces Washington apples. However, apple trees have been known to cross-pollinate with pear trees while experiencing blooms at the same time.
Although the apricot tree is self-pollinating, it thrives well when planted in groups of two or three trees to improve the rate of pollination. Nanking cherry trees also help in cross pollination with apricot trees. In colder climates an apricot tree may have trouble producing fruits unless cross-pollination occurs.
The blueberry bush is another primarily self-pollinating plant that can be improved upon with cross-pollination. Planting two or three blueberry bushes together can help in yielding larger, darker and more abundant berries. A cold weather plant, the blueberry bush's yield can be scarce when cross-pollination isn't implemented.
In order to produce fruit, both a male and a female kiwi tree must be planted together in order to cross-pollinate. One male plant can cross-pollinate approximately 10 female kiwi plants, but a female plant must always accompany a male in order to thrive successfully. Tropical climates are best for planting a kiwi orchard, as cold weather can kill both the male and the female plants.
A jostaberry tree is the product of cross-pollination between a gooseberry bush and a blackberry bush. Although both fruit tree families are self-pollinating, when grown in groups of two or more together, the cross-pollination creates the unusual, but very sweet berry.