Collect Your Equipment
Pruning thorny rose shrubs requires sturdy, thorn-proof gloves and safety glasses to protect your eyes. Look for elbow-length gloves at garden centers. You also need a pair of sharp hand pruners for canes up to 1/2 inch in diameter. Use long-handled loppers or a small pruning saw to cut larger stems and to reach into the center of dense shrubs.
Inspect Your Rose Plant
First, identify all dead and damaged canes. Next, locate long thin canes and canes that grow from below the graft union, if the plant is grafted. Lastly, look for canes that rub against or crowd each other, especially if they're growing through the center of the bush.
Determine Where to Cut
Prune canes back to fat, pink buds that face the outside of the shrub. Cut the spindly canes back by half their length or to 2 to 3 feet long. Cut or break off canes completely that grow from below the graft union. Remove diseased canes, and those that rub or crowd, back to healthy, outward-facing buds. If you see brown tissue in the center of a cane when you cut it, prune a little farther back until the tissue is clear and healthy.
Make the Right Pruning Cut
Make your cut about 1/4 inch above a healthy bud and at a 45-degree angle. The bud and the high point of the cut should be on the same side of the cane so that water will drain away from the bud. To prevent the spread of disease, clean your pruning tools between shrubs with a mix of one part bleach and nine parts water.
Remove Spent Flowers
To encourage repeat flowering, use hand pruners or scissors to remove flowers as soon as they finish blooming. Cut each flower stem back to a leaf with 5 to 7 leaflets and a healthy bud.
Timing Tips for Colder Climates
In cold-climate areas, wait to prune until the buds just begin to swell in spring. It's easy at this time to tell the difference between healthy canes and buds and those that didn't make it through the winter.
Fertilize roses after spring pruning to encourage strong new growth.
Article provided by the National Gardening Association