In Houston the traditional time to prune our roses is Valentine's Day. Exactly how much to prune depends on the kind of rose about which one is talking.
Hybrid Teas
Floribundas
Climbers
Miniature roses
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Non climbing hybrid tea roses are pruned back to about knee high. Try for three to five thick canes. I cut off canes smaller than the diameter of a pencil at the bud union if the rose has at least three thick canes. (If there are less than three good canes I get out the shovel and prune with it.)
Always cut back to about 1/4 inch above an outward facing bud eye. Prune with a slanting cut so that the water drains away from the center of the bush.
There is much debate about the necessity of putting pruning paint on the cut. Most rose growers in Houston don't advocate pruning paint. However, I often dab a little Elmer's white glue on the new cut. To me, this seems to help prevent die back at the cut area. I do this only on canes that are larger in diameter than a pencil.
Floribundas are pruned the same as hybrid teas, except one leaves more canes from the bud union than with hybrid teas. Be sure and eliminate crossing canes and canes growing inwardly. You want the canes to flare out from the bud union. for a page on tips for pruning floribunda roses in Houston, click here.
If your climber repeats during the season you should lightly prune it in mid February. If the climber is a once-blooming climber don't prune it until after the spring bloom.
There is much more latitude in pruning miniatures. Some rosarians write of using electric hedge clippers to prune their miniatures. I'm sorry, but I can't go that far. I prune my miniatures back to about 12 inches, and try for outward facing bud eyes (although that is less critical with minatures than it is with hybrid teas).
OGR's do not need to be pruned. Let them go. Prune only for purposes of grooming (i.e., to control wayward growth, or if they get too big for the space you have allowed). If you must prune, do not prune them until after their first flowering of the spring. Some OGR's only bloom in the spring. Prune them in February and you will lose your blooms!