Tree pruning increases light, benefiting fruit

Q. I've heard that winter is a good time to prune trees, is this true still for fruit trees?

I have a large old tree on my property that probably hasn't been pruned in over 10 years. It is unsightly, messy and just produces small fruits. How would I go about pruning my tree this winter and are there any major differences between pruning ornamental vs. fruit trees?

A. For most ornamental and fruit trees, winter is the perfect time to prune.

Deciduous trees, which lose their leaves, are bare at this time, allowing you to get a good look at the structure and branches of the tree. There are also less pests and diseases in the winter, so there is less of a chance of wound infection through the pruning cuts. In Northern Illinois, anytime between mid-November and mid-March is a good time to work on pruning.

First, make sure you have a good idea of why you are pruning. It is going to be important to keep that in mind while you are working and for your plan moving forward. Is it for overall shape? Or maybe you are interested in encouraging more fruiting? Either way, throughout the process, be sure to take breaks, step back, and look at the overall tree to make sure you are still on the path toward your long-term goals. Many old trees will need three to four years of heavy pruning to get them to a good point.

The first thing to do, with both fruit and ornamental trees, is to remove any dead, damaged or diseased wood. This can sometimes be hard to decipher in the winter, but start by removing broken branches and those that don't grow leaves anymore. Next, prune the suckers (at the base of the tree, coming from the roots) and water sprouts (on branches, thin, and grow straight up).

Now you can start thinking about shape and overall function of the tree. Start by identifying your central leader, which is the dominate shoot in the center of the tree. Your tree might have a clear leader, be open in the middle, or even have a leader that starts out as defined and then divides further up the tree.

You can then start removing crossing and rubbing branches and branches that are growing downward. From there start thinning the canopy starting from the center to increase air circulation. In general, do not remove more than 10 to 20 percent of a tree's branches in one season.

For most home gardeners, following this procedure will result in healthier trees for both ornamental purposes and fruits. For fruit trees like apples and pears, it is especially important to identify a central leader, strong scaffolding branches, and to continue cutting water sprouts that might grow in the summer after a heavy prune.

If you are getting small and frequent fruits, you can also thin the fruit throughout the season to encourage larger growth.

Getting your trees back to a manageable state can be a daunting process, but with a clear plan and care with pruning, you should have better air circulation, light penetration and fruits. Don't forget to thoroughly clean your tools before and after and be sure to make your cuts just next to the branch collar (where the trunk meets the branch).

— Gemini Bhalsod

University of Illinois Extension Horticulture Educator

• Provided by Master Gardeners through the Master Gardener Answer Desk, Friendship Park Conservatory, Des Plaines, and University of Illinois Extension, North Cook Branch Office, Arlington Heights. Call (847) 298-3502 on Wednesdays or email northcookmg@gmail.com. Visit web.extension.illinois.edu/mg.