Roses are a classic in any garden, but if your client wants to get the most out of them, it is important to stress the value of pruning.
“Every plant needs a little bit of maintenance,” said Jacques Ferare, rose program manager with Star Roses and Plants. “There’s no such thing as a maintenance-free plant. Even perennials and shrubs may need to be sheared back in the spring to look their best.”
There are many different types of roses and each has its own specific pruning techniques. Timing can vary a bit as well.
The goals, however, are always the same: removing diseased or damaged wood, increasing air circulation, shaping the plant and encouraging growth on flowering wood.
As for when to prune roses, the common answer is when the forsythia bloom, but on a calendar this can be anywhere from mid-to-late February to mid-April depending on your location. The main goal is to prune just before the buds break dormancy. Instead of looking for forsythia, you can look at the rose buds. If they are beginning to swell, it’s time to prune.
When pruning, cut at a 45-degree angle about ¼-inch above an outward-facing bud. The cut should slant away from the bud.
Here is an overview on the different categories of roses and the preferred method of pruning for each.
This is a diverse group of roses and they tend to be larger than modern bush roses. These roses can be repeat flowerers or flower once during the summer. For the shrub roses that only bloom once, during the late summer – after flowering – clear one or two of the older, unproductive branches in the center to prevent crowding. If the base becomes bare, remove one or two stems at the base level to encourage growth there.
For repeat-flowering shrub roses, reduce new growth in the late winter by up to one-third. Side shoots should be shorted to two or three buds, while some of the older main stems should be cut back to the base to encourage growth. Deadhead spent blooms during the summer for more flowers.
Climbing roses are typically pruned between December and February. Remove any dead or diseased branches and clear away flowered side shoots by two-thirds of their length. If the plant is particularly tangled or overgrown, cut away old branches from the base to promote new growth.
If you’re trying to renovate an overgrown climbing rose, cut away the oldest canes, with five to seven of the strongest left alone. Shorten side shoots on the remaining branches and prune back the tips by one-third to one-half to encourage branching.
Hybrid teas and floribunda have similar pruning techniques. Hybrid teas are large-flowered and should have the strongest shoots shortened back 4 to 6 inches from the base. Less vigorous shoots should be shortened 2 to 4 inches from the base.
Floribunda are cluster-flowered and their stems are left longer with more buds that allow the shrub to form its characteristic mass of blossoms. The strongest shoots should be pruned down to within 10 inches or one foot of the soil level, while less vigorous shoots should be cut back more severely. Older stems can be pruned back hard from time to time to encourage stronger growth at the base.
Shrub-type groundcover roses rarely need routine pruning, but when they have extended their boundaries hard prune upright growths back to their designated area. Shorten side shoots back by a few buds and reduce the strong shoots by one-third.
For spreading, rambler groundcover roses, it is best to shorten the side shoots in the summer after flowering to prevent the plant from getting out of hand. If the groundcover does become unruly, it can be renovated by pruning near to ground level from the base in the late winter.
These dwarf roses are often no more than 10 inches tall and require the least amount of pruning of the varieties. Remove dead or twiggy growth, shorten back weak growths and occasionally prune some of the older growth to near soil level to promote growth near the base.