How many fruit trees do I need to plant to have fruit?
This question comes up each year as people start thinking about planting fruit trees. Most have heard you need to plant two trees to have fruit, often assuming you need a “boy” tree and a “girl” tree. This is not quite correct. You do need two trees for producing many tree fruits but it has nothing to do with gender.
Most fruit trees are neither male nor female as their flowers contain the reproductive structures, stamens and pistils, for both sexes. These flowers are referred to as perfect. However, the individual trees of some fruit tree species will not accept their own pollen and for these you do need two trees. These are called self-sterile fruit trees and include apples, pears and hybrid plums cultivars.
To obtain fruit from self-sterile trees, you must plant two trees, but these trees must be two different cultivars, not merely two different trees. If you want fruit from a ‘Haralson’ apple, you have to plant another apple cultivar near it, ideally within 50 feet. Just having two ‘Haralson’ apple trees will not result in apples, only flowers. To further complicate the process, if you have a ‘Haralson’ and a HaralredR apple tree you will still not receive fruit as the HaralredR originated from a ‘Haralson’ apple tree so they are too closely related to pollinate one another. Two other popular apples, ‘Fireside’ and ‘Connell Red’ share the same problem, they cannot pollinate one another. Another challenge to selecting apple cultivars are you must not only have two different, and unrelated, apple cultivars, but the trees must be blooming at the same time. A ‘State Fair’ apple tree, in which the fruit ripens in August, may be finished blooming before a ‘Haralson’ which fruit ripens in early October, begins to flower. Usually it is not a good idea to assume an early season apple will pollinate a late season.
Pears and hybrid plum bloom within narrow time periods so the flowering of their many cultivars will generally overlap. However, some cultivars are better pollinators than others and some trees do not produce viable pollen at all. One of the best pollinators for plums is ‘Toka’ and is a good choice for any plum orchard. ‘LaCresent’ and ‘Superior’ are two popular plums but these share a similar parentage and cannot be used to pollinate one another.
Most pear cultivars are compatible with one another, the two exceptions being ‘Gourmet’ and ‘Luscious’ which are pollen-sterile. This means that neither of these trees will serve as a pollen source but will accept pollen from another cultivar.
Apricots are generally not self-sterile but the two cultivars frequently planted in our region ‘Moongold’ and ‘Sungold’ must be planted together to ensure fruit production. The majority of other apricots are not self-sterile but many are not as hardy to our region.
There are also fruit trees that are self-fruitful rather than self-sterile. These fruit trees are able to pollinate themselves so you only need the one tree to have fruit set. The fruit trees in our region that are self-fruitful include European plums and sour (pie) cherries.