When should I prune my roses and other perennial shrubs?
The general rule for shrubs is that they should be pruned after they have bloomed. For summer or fall bloomers, prune them after they have gone dormant after the first freeze. For spring bloomers like forsythia, prune them in the late spring after blooming is complete. For all shrubs, first remove any branches that are crossed, damaged, diseased or dying. Also remove branches that are older and woody. After removing problem branches, adjust the height of the plant if needed. The general rule is to not remove more than one-third of the plant each year. It is better to prune a little each year than to wait several years and try to correct out of control growth by severe pruning of the plant.
Pruning roses is a little different and depends on the type of rose. During the blooming season you can remove the spent blooms (deadhead) to promote more blooms. You should stop deadheading in August and wait until cold weather has caused dormancy and then you can remove the spent blooms, if desired. Do not prune the stems until you see the buds start to swell in the spring (about the time forsythia blooms). The new varieties bloom on new wood. Everblooming and Floribunda roses should be pruned hard (half or more of the plants height removed). Leave 3 to 5 healthy canes evenly spaced around the plant. Hybrid Tea and Grandiflora should have dead or weak wood removed to create an open vase shape. Remove center stems or any crossing branches. Prune remaining branches down to 18 to 24 inches. All cuts should be angled toward the inside with a bud facing outward at the top.
If you have questions concerning this topic or related topics, please contact the OSU Extension Center, 14001 Acme Road, corner of MacArthur and Acme Road in Shawnee or 273-7683. You can also check our website: http://countyext.okstate.edu/pottawatomie/ and look for information available online.