Repeat flowering roses should be pruned anytime from late January through mid-February.
This pruning is especially important for the popular hybrid tea and grandiflora roses, but all types of repeat-flowering roses benefit from pruning. Without the annual pruning, roses generally become leggy, less vigorous and unattractive and do not bloom as well.
To prune, use sharp bypass pruners on your roses. Should you need to cut canes larger than one –half inch in diameter, you should use bypass loppers. It’s a good idea to wear a sturdy pair of leather gloves and long sleeves to protect your hands and arms from the thorns.
When pruning Hybrid Tea and Grandiflora Roses:
First, remove all diseased or dead canes and weal or spindly canes that are the diameter of a pencil or less by cutting them back to their points of origin. A good rose bush should have 4-8 strong, healthy canes the diameter of your finger or larger after this first step.
Cut back the remaining canes to about 24 inches from ground level. When you prune a cane, make the cut about one-quarter inch above a dormant bud or newly sprouted side shoot. Try to cut back to buds that face out, away from the center of the bush. The new shoot produced by the bud will grow outward, opening up the bush for light, air and orderly growth. This may seem picky, but it makes a difference.
When pruning other types of ever-blooming roses:
In general, roses in this category have more pleasing shapes without severe pruning. But, pruning is still needed to stimulate vigorous growth and control the size and shape.
First, remove any dead or diseased canes.
To lightly shape the bushes, selectively cut back individual branches to improve the overall form.
If a bush is overgrown, it will tolerate hard pruning to get back into shape. As a rule of thumb, these roses are cut back about 1/3 to ½ their height, depending on the situation.
Long, especially vigorous shoots that have grown well beyond the rest of a bush and make it look out of balance may be cut back more than the rest of the bush.
Young bushes planted within the past year or two likely will not need drastic pruning but they may be cut back lightly to encourage a full, bushy plant.
When pruning once-blooming roses:
Once-blooming roses should not be pruned now in late winter. Once-blooming roses produce their flowers on growth made the previous year. If they are pruned back now, they will produce few, if any, flowers.
It’s far easier for you and healthier for the rose bush if you prune at least once a year. It is very difficult to properly prune a rose bush that has been allowed to grow for several years without pruning. There’s another prune push in late summer-around late August.
Adapted from Horticulture Hints, LSU Ag Center.