The beauty of climbing roses is also the challenge of climbing roses. Rose canes can grow 25 feet long and have many entangled canes. It is best to keep climbing roses cut back each year to prevent tangling and excessive growth. Do not prune climbing roses for the first two to three years as they establish the top growth needed to produce flowers. Once the long canes are established, only lateral canes need pruning. New roses bloom on lateral canes which grow out of the main structural canes. Prune climbing roses in late winter to early spring before new growth appears.There are several steps to cutting back climbing roses.
Remove all dead, diseased or spindly branches. Cut them down flush with the cane they grow from. Remove all older woody canes which have failed to produce blooms in the previous season. Cut back all canes which are growing cross-way through other branches.
Prune with a design structure in mind. Step back from the plant and take a look at the trellis, wall or fence structure the rose grows on. Continue cutting down canes which do not conform to the shape of the trellis or horizontal wall design. Roses trained to a pillar or post look best with two or three canes wrapped around it.
Cut lateral branches back to two to five buds. Make the pruning cut 1/4 inch above a bud. New roses bloom on these horizontal branches. The more horizontal branches, the more flowers. Choose younger, more vigorous branches over older ones.
Support remaining canes and branches with plastic ties or twine. Climbing roses have no tendrils to cling to a trellis or wall so they need artificial supports. Plastic ties that stretch will not cut and harm the branches.
Remove suckers from the plant base. Hybrid climbing roses may have suckers grow from the original rootstock. They look like a knobby, swollen mass near the soil surface. Cut these down flush with the main root. If these suckers are allowed to grow they will eventually overwhelm the hybrid upper grafted portion of the plant.