Pruning Climbing Roses
Pruning climbing roses and ramblers can be confusing when going to the books for direction. The lines of distinction blur when we talk about roses with all of the hybridization between lines. A rambler may be to another a climber, and a climber may someone else’s rambling musk, and depending on the book you read you find different tips on care. Under the heading of climbers falls a mish-mash of roses. The most important bits of information to determine about your rose is when is its bloom time, and how often-only once, a perpetual bloomer or repeat bloom in the fall? An easy place to start sorting out the climbers is with the Climbing Hybrid Teas.
The Climbing Hybrid Teas are usually climbing sports of bush-form Hybrid Teas. They produce long canes (6-10’) which do not end in flowers, but rather bloom on shorter laterals that grow off of the main canes. Under this heading you would find Climbing Dainty Bess, and Climbing Peace. These laterals should be shortened after they bloom during the growing season to get a repeat bloom. They should be allowed to grow to their height and become established for the first few years. At their height, bend the canes so they run horizontally, training them onto a wire or across an arbor. When a climbing rose main cane is forced into a horizontal position, it will grow laterals, which grow vertically and become the flower producing stems. Prune these laterals to 6 inches long, or 3 to 5 buds while dormant, and they will produce flowers for many years. These types of roses tend to put on more top growth and not produce new basal growth canes as easily as do the bushtypes. To encourage new growth on a mature climber, cut back an old cane to the lowest lateral growth, and consider that as the new main cane. Pillar roses are treated in the same way as the Climbing Hybrid Tea rose.
If you know the name of the rose, you can usually find out how it grows, when it blooms and how and when to prune. If you don’t know the name, determining a climber vs. a rambler is often a difficult call. There is another large group of climbers other than Climbing Hybrid Teas or Ramblers, called Repeat Blooming, Large Flowering Climbers. In this group we find Climbing New Dawn and offspring of Rosa wichurana, which are repeat blooming climbing roses. This terminology was coined by hybridizers in the early 1900s to describe any repeat blooming rambler that had large flowers, much like we are using the term "English Roses" today to describe a certain look, but catching all sorts of lineage. Generally, a climber is stiffer in habit, with canes that can be trained to structures, arbors, and trellises while still young and malleable. They will often be remondant- meaning they will flower more than once a season, and bear medium to large flowers in clusters or as a single bloom. A rambling rose will have more lax canes, often thornier, and will sucker more freely, making a mat of bramble like growth. They are seldom remondant, and blooms are smaller and in clusters. The rambler is readily adaptable to training on fences, and over and through deciduous trees, and over buildings.
A climbing rose should be allowed to attain the height desired before any pruning begins, which means leaving it for 2 to three years untouched. When the rose reaches its desired height, start training it horizontally to encourage production of sideshoots off of the main canes. Most climbers flower well with little pruning besides removal of dead, diseased or weak growth. The main canes only need pruning back to keep it from traveling too far, and laterals can be lightly pruned back 3 to 6 inches or 3 to 4 buds. After at least three years, you can remove a few of the oldest canes to induce new main cane growth. In this way, the rose will always have a majority of 2 to 3 year old wood from which the flowering laterals grow.
The rambler blooms only once a year and can be pruned immediately after its bloom for the plant to grow new canes. The rambler blooms midsummer on one-year-old wood from laterals of long basal shoots that grew the previous season. A rambler unpruned becomes a thorny briar patch, wild and unchecked. To contain a rambler and keep its appearance sweet, it should be pruned hard back to the ground after blooming. Another method of pruning a rambler is like that of training a climber, on a wire wooden trellis, stretching out the canes horizontally and tying them in place, and pruning back laterals to 2 to 4 buds. There are not many true ramblers, although you may see a ‘Dorothy Perkins’ here and there.
Carol de Maintenon is a member of Garden Writers of America and owner of Benicia Garden & Nursery.
