HOW AND WHEN TO PRUNE ROSES
In Pacific Northwest Gardens
by Joelle Steele
Roses are plants that have been carefully bred and cultivated for more than a century. To ensure that they are always blooming their best, they need to be properly watered, fed, and pruned. Most people — and our Pacific Northwest environment in particular — provide the water and the fertilizer. But pruning is frequently neglected or is done incorrectly and at the wrong time. As plants go, roses are a pretty hardy lot. But if they are not pruned correctly, they will ultimately begin to deteriorate, succumbing to pests and diseases, and producing far fewer and often much smaller flowers. Eventually, they will become very ragged-looking and woody, then die.
The majority of today's modern roses (dating from 1867) are classes that were created from old or antique roses (from pre-1867) such as damasks, gallicas, albas, centifolias, teas, noisettes, bourbons, and all their various hybrids. Among the modern roses you might find in your garden are the following classes:
Polyanthas. Hardy, low-growing to about 2 feet, large clusters of small flowers, not usually very fragrant, but bloom continuously throughout the growing season.
Hybrid Teas. Tall, long-stemmed, large flowers, frequent bloomers, many colors available, and many fragrant varieties.
Floribundas. Originally hyrids between polyanthas and hybrid teas. Hardy, large bushes, clustered flowers, summer bloomers.
Grandifloras. Crosses between hybrid teas and floribundas. Tall up to 6 feet or more, larger flowers than floribundas, long stems like hybrid teas, beautiful colors.
Rugosas. Hybrids of hybrid teas and Rosa rugosa. Very hardy, disease-resistant, require very little care.
Miniatures. Small plants, usually not much more than 8" to 12" in height, very tiny flowers, spindly stems, frequently grown in containers.
Ramblers. A form of climber that has very pliable canes and needs a support to keep them from falling onto the ground.
Climbers. Have very tall canes that need a support in order to grow upright and prevent the canes from breaking.
WHEN TO PRUNE
The hybrid teas, grandifloras, and floribundas should be pruned in the spring once snow has stopped and freezing temperatures have past. There is an old saying that you should only prune a rose when the forsythia is blooming, so you may want to keep an eye out for the brilliant yellow forsythias in your garden or neighborhood. Pruning your roses too soon can cause damage and, in that event, you may have to prune again. Some roses, such as ramblers, should be pruned right after they finish blooming, and climbers should generally be pruned in the fall before cold weather sets in.
TOOLS AND PRUNING TECHNIQUES
Fortunately, you don't need anything fancy to prune a rose, just sharp hand-pruners and sturdy gloves to protect you from the thorns. If some of your roses are very large and have thick canes, you may also need a small garden saw and a pair of loppers.
As with all pruning, make your cuts at 45-degree angles above an outer bud, with the highest point of the cut just above that bud. This will promote healthy new growth and better flowering.
Begin the pruning process by removing any dead, damaged, spindly, or criss-crossed branches. If you're trimming back an old plant with heavy canes, remove one or two of the oldest canes each year. Next, prune back all the remaining healthy canes. Try to keep the center of the plant clear of canes and branches, because roses need good air circulation.
The lower you prune a modern rose, the stronger the new growth will be. For your average hybrid teas, polyanthas, and floribundas, you should cut the canes down to about 10" to 16" in height. With the taller roses, such as some hybrids and grandifloras, you should cut the canes down to 18" to 24" in height. If you're pruning a "standard" or tree rose, prune the branches back to about 8" to 10" from the base of the crown at the top of the trunk. With miniature roses, just remove all the dead growth and the hips — those round, fruit-size seed pods that form after blooming is finished.
Some roses require additional pruning strategies at different times of the year:
Ramblers produce clusters of flowers once per year on multiple long canes. Their most beautiful flowers tend to appear on the previous year's growth. They need to be tied to some kind of support so that the canes don't break. They should be pruned right after they are done flowering. At the same time, remove some of the oldest and largest canes. When you are pruning is the best time to secure the canes to their trellis or other support.
Climbers are similar to ramblers, but their canes are much bigger and heavier, and they produce their best blooms on canes that are 2 years old or older. Like ramblers, they should be secured to a support. Any side shoots should be cut back by about 5" to 6" right after flowering is completed. Since some climbers bloom more than once per year or bloom more or less continuously, they should all be pruned in the fall before it gets cold. Remove a couple of the oldest canes to leave room for new ones.
Old or antique roses do not require much pruning. In fact, if you leave them unpruned, they will usually grow into a nice shape all by themselves. In general, you can do some pruning on them as needed, such as removing dead or damaged branches, or removing any long stray branches you don't like. To encourage more blooms, you can trim as you see fit, but not as drastically as with modern roses.
DEADHEADING AND MAINTENANCE PRUNING
With roses that bloom more than once per year, deadheading is an important form of pruning and encouraging new flowers. To deadhead, remove dead flowers immediately, cutting back only as far as just above the node of a compound leaf that is composed of five leaflets. For roses that bloom only once yearly, deadheading is done for purely cosmetic purposes. If at any time you see damaged canes, remove them entirely or cut them back just above an outer node. If you see branches that have died back, remove the affected parts of the branch just above an outer node.
This article last updated: 02/21/2013.