August 09, 2022

Down the Garden Path: Choosing apple trees for size and pollination

January is not too early to start to plan for a new home orchard or to consider replacements for aging fruit trees in an existing home orchard. There are different kinds of fruit trees to consider: apple, cherry, peach, pear and plum.

Since we are in northern Illinois, apple likely is the main fruit tree grown in backyards because it is the hardiest. For the home orchard, apple trees are a good starting point. Once you have a good handle on apples, expanding to other fruit trees will be easier.

When you shop the fruit tree catalogs or visit your favorite retail garden center to find out what cultivars or varieties they will carry this spring, homeowners should consider dwarf apples, as yard space may be limited. Dwarf apple trees are naturally smaller than their full-sized siblings and are much easier to train, prune and maintain.

Apple trees are dwarf naturally or because fruit tree growers graft or bud them to a dwarfing rootstock, limiting the overall size of the tree. If they are naturally dwarf, then the apples listed will be a “spur-type” tree. There are many examples of spurs available to us: Empire, Red and Yellow Delicious, Macintosh, Rome, Winesap and Early Blaze are a few.

It should be noted that the catalogs will list a mature size, considerably smaller than the full-sized version, yet the ultimate size of your dwarf tree is really up to you. If you start to train your trees too late or do not prune correctly, the dwarf apple tree will be much larger than you wanted or expected, yet still much smaller than a full-sized tree.

Another very important key to selecting your apple trees will be pollination. Fruit tree catalogs will suggest which apple varieties will be the best pollinators for the varieties you wish to grow. It is critical that you have two varieties blooming at the same time for a strong fruit set. Apples for the most part are considered to be “self unfruitful,” meaning that pollen from other flowers on the same tree or from another tree of the same variety will not pollinate itself.

A possible exception to this rule is if you have an ornamental flowering crabapple in bloom at the same time, then pollen from the flowering crabapple will pollinate the apple tree. So if you live in an established subdivision and you or a neighbor has a flowering crab apple in the front or side yard or an apple tree of a different variety that blooms at the same time, you do not have to plant a second apple tree for pollination purposes, which will free up space in your backyard.

Further compounding the pollination story is that there are trees containing sterile pollen. You will get apples from that tree, yet the pollen-sterile tree cannot serve as a pollinator for other apple trees. Read the tree description and pollination needs carefully before ordering. Ask plenty of questions at the garden center before making a purchase.

• Richard Hentschel is a Horticulture Extension educator with University of Illinois Extension, serving DuPage, Kane and Kendall counties. This column originates on his blog at go.illinois.edu/overthegardenfence. To get tips from Hentschel, watch his “This Week in the Garden” videos on Facebook and YouTube.