I am hoping for some warmer weather so I can do some winter pruning. Winter is a perfect time to prune most trees and shrubs.
Correct pruning is an essential maintenance practice for ornamental trees and shrubs. However, most homeowners regard pruning with considerable apprehension. Pruning is not difficult if you understand the basics and learn why, when, and how to prune.
There are many reasons why we prune landscape plants. In early stages we often prune to develop a desired form. In later years, pruning maintains form and stimulates growth. Many homeowners prune too much simply because they selected the wrong plant for the site. If you want a round shrub, plant a rounds shrub. Similarly, use a short plant or a narrow plant if space is limited.
My winter pruning plans include renovating several shrubs that have gotten a bit scraggly looking. I need to remove old stems from lilacs, dogwoods, and honeysuckle as well as thin some trees with crossing branches.
When to prune is simple. Prune when the saw is sharp! The only real exception to that are oaks, which must be pruned in winter to avoid disease transmission.
Flowering shrubs need pruned at certain times to assure good flower display. It won't hurt them to prune at other times; you simply won't get flowers that year. As a rule of thumb we prune early flowering shrubs (such as lilac) after they flower since they formed their flower buds last fall on old wood. Shrubs, such as roses and hydrangea, form flower buds on new wood after growth begins in spring and thus can be pruned now.
Explaining how to prune is a bit more complicated. I often start by removing stems with the 3 D's: dead, damaged, or diseased. After that I look for watersprouts, suckers, crossing limbs, and girdling roots. Ideally, create branch angles on trees greater than 90 degrees for stronger limbs.
Most importantly, DO NOT LEAVE STUBS. Always make pruning cuts all the way back to a bud or branch. This means not topping trees, which creates a much weaker tree that is susceptible to breakage from wind, ice, and snow. Many people top weak wooded trees, hoping it will make their homes safer. A better solution is to do proper, selective pruning or better yet to plant slower growing, stronger trees to start with.
To learn more attend Gardeners' Big Day on March 29th at Dickson Mounds Museum where horticulturists from Boehms Garden Center will give an outdoor pruning demonstration. Or, consider purchasing our booklet "Pruning and Care of Trees and Shrubs" for $12.00 from http://pubsplus.illinois.edu.
Bundle up and go prune!