While waiting for warmer weather to arrive, pruning of shrubs is a spring garden chore that can be performed. Remember to wait before pruning spring-blooming shrubs until after they have finished flowering as not to remove flower buds. Be aware that a few summer-blooming shrubs, such as some hydrangeas, also bloom on old wood, and if pruned before flowering their blooms will also be removed. But summer-blooming shrubs that bloom on new wood can be pruned as needed in the early spring before the new bud growth starts.

Pruning shrubs while dormant makes for an easier task, as without leaves, branch structure and the overall shape of the shrub is more easily observed. Branches should be cut back to an outward facing bud, about one-fourth inch above the bud attachment, to encourage new growth to develop outward. A pruning cut made too closely to a bud may cause injury to the sprout. Leaving too much remaining branch above a bud when pruning, not only looks bad, but also may encourage pests to locate within the dying wood.

Make pruning cuts at a forty-five degree angle which slopes away from the bud. Cutting away from buds in this manner will help avoid creation of an area where water may collect which can cause disease.

Before the overall shaping of a shrub, look for any branches that are dead, damaged or diseased and remove those first. Next, check for any branches that are crossing each other or rubbing together and prune those out. Stand back away from the plant to check the overall form, and then prune as needed to shape or restrict growth.

Be sure to use pruning shears with sharp blades. Cuts made with dull blades will produce ragged cuts that can attract disease and insects.

Pruning helps not only to improve plant health by removal of diseased, dead or insect infested branches, but also helps increase flower production by limiting number of branches.

Did you know? Plant terms to learn: Herbaceous – perennial plants with soft, green, non-woody shoots that die back to the ground each winter. Woody – ornamental plants (i.e. shrubs & roses) that survive winter both above and underground.

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Questions? Contact McCormick at yvonne@iastate.edu for information or advice.