If your fruit trees aren’t bearing fruit, then you may have problems with cross pollination. Some varieties won’t fruit unless they can be cross pollinated with another variety. Cross pollination occurs when bees carry the male gametes (pollen grains) to the female gametes (ovules) from one tree to another. But with some fruit varieties, male and female trees are required so nature can takes its course.
Other creatures also carry pollen, such as wasps, butterflies, hummingbirds and fruit bats. But bees are by far the most efficient. A study by the University of Bristol in 2015 showed that other carriers were not as successful as bees. So if you have male and female trees and still no fruit, it may be that you need bees in your orchard.
The trees that require cross pollination are apples, pears, cherries and plums. If you are planning to put in new trees, check with your neighbors to see what varieties they may be growing. You may not need to plant more than one variety of a fruit if cross pollination can occur from your neighbors’ trees.
Even then, it is not as simple as just planting two different varieties. Depending on the variety that is your first choice, you will need to choose another variety that cross pollinates successfully with yours.
For example, the Jonathan apple will cross pollinate with a Granny Smith, and these are actually two of the best apple varieties to plant, as you will have apples for eating and apples for cooking that are compatible with each other. If you want two varieties of eating apples, Gold Delicious will cross pollinate with Jonathan.
Cherries that are not self-fertile may require more than one variety for pollination. Other varieties, happily, are self-fertile and do not require cross pollination to bear fruit. These include the popular Celeste and Sweetheart. Before you plunge in and buy a young tree, check with your supplier whether your favorite variety is self-fertile or needs one or more different varieties for cross pollination.
The Japanese plum variety Satsuma is an excellent cross pollinator with other varieties such as Santa Rosa, Mariposa and the thrillingly named Ruby Blood. If you want to grow European plums, they won’t cross pollinate with the Japanese, but most European plums will cross pollinate with each other.
Pears require a lot of cross pollination to bear fruit. You will need two different trees at the least, and as they grow to around 40ft, you should choose dwarf varieties for a small garden. Cross pollination is an issue, as most insects are not attracted to pear blossom. So a good supply of bees is a priority if you want good fruit.
Just remember, a thriving orchard needs sunshine, good drainage, fresh air and bees – lots and lots of busy bees.