How to prune your roses
Pruning the roses is not a mysterious art form. Roses are deciduous shrubs that flower on new stems, called canes, that grow from the base each year. As canes age, they lose vigor and produce fewer and fewer flowers. An old, neglected rose bush is an unsightly tangle of dead wood and old canes. To continue blooming profusely, rose bushes must be pruned once a year to stimulate the growth of new canes.
Pruning also lets light through to the "bud union" at the base of the plant. Most roses are bud-grafted, and the big, wood knob at the base is the graft. A rose produces more and healthier canes if its bud union gets plenty of sunlight in the late spring and early summer. Remember, though, that the bud union can be severely damaged by snow and frost. In colder regions, cover it with soil and mulch from first frost to last.
Most roses bloom in summer and should be pruned in October, just after buds begin to appear.
If you prune too early, you'll stimulate premature growth that is vulnerable to frost damage. If you prune too late , you will waste energy the plant has put into early-spring budding and leafing. The ideal time is after the last killing frost, when buds halfway up the most vigorous shoot are beginning to swell, and buds near the tip have grown to about ¼-inch.
Roses that bloom on the previous year's wood should be pruned after they are finished blooming. A few roses bloom on both new and old wood. Prune each type of flowering wood as if it were a separate plant.
Seal all large pruning cuts with tree paint or rose paste to prevent disease and speed healing.
If you have a diseased rose plant, make sure to dip clippers in alcohol after pruning to prevent spread of the disease.
Pruning with Planting
If you buy a rose bush with a root ball wrapped in burlap or one grown in a container, the only pruning you need to do when planting is to cut back any dead, diseased, or damaged growth.
If you buy bare root roses, prune away any broken or mangled root tips. Then remove all twiggy growth from the top of the plant.
Make sure to cut the canes back to within 6 to 12 inches of the base of the root union.
First, be sure to have on hand sharp pruning shears and a pair of stout garden gloves; most roses have very sharp thorns and are much easier to prune if you're not constantly worried about being pricked.
Begin by removing dead, diseased, and damaged canes. Dead wood is brown and dry inside, even when it's green outside.
Next prune away any crossing canes and lateral branches that may rub together. Disease and pests enter where bark is abraded. Remove crossing growth from the center of the plant to allow light into the bud union. A vase shape is the ideal skeleton for most rose bushes.
With young plants, that's all the pruning needed. On plants three or more years old, keep pruning. Cut away about one third of the oldest growth. Start by removing wood three or more years old. Then cut two-and-one-year old wood back to the height you want to maintain.
To distinguish between new wood and old, look at the color of the canes. One-year-old wood is green with green thorns and vigorous green leaves. Two-year-old wood is brownish-green, and the thorns begin to look dull. Other wood is brown or gray or black.
When pruning an old cane, cut it back to where young, green wood is showing. If a cane is brown or black from tip to toe, remove it at the bud union. Leave no stubs. Cut back to an outward-facing bud, and make the cut ¼-inch above the bud and facing away from it.
For a balanced shrub, leave canes on the east and north sides of the plant 2 to 4 inches longer than those on the south and west sides. The latter will get more light and grow longer, catching up with the other canes by midsummer.
Remove suckers. Don't just cut them off above ground. Trace them back to their roots and pull them out.
Check the number of buds at the nodes of the remaining canes. There should be only one bud at each node. If there are several, rub away all but one with your finger.
You should now have a vase-shaped skeleton consisting of two to six young canes arising from the bud union. Four canes are ideal. Each cane should have an outward-pointing bud about ¼-inch below its tip. The canes should be no more than 30 inches high on a mature shrub, unless you want a taller plant.
If you want your shrubs to produce a few large blossoms, prune more severely, removing more canes and cutting the remaining ones lower. If you want more, smaller blossoms, prune lightly.
During the flowering season, pruning is limited to removal of spent flower clusters. This prevents the shrub from producing hips (fruit and seeds) and encourages better blooming next season. Remove flowers by cutting back the stem bearing them to the first strong, outward, facing bud. These buds are located just above a leaf with five leaflets. Leaves with one, two, or three leaflets tend to have weak buds.
Don't just nip off the flower. If you do, the weak growth just below the spent flower will produce weak, straggly growth.
Cut above the second 5-leaflet leaf from the top.
There are many different roses available, and there are minor difference in how each should be pruned for the best effect and the healthiest plant.
Hybrid teas and hybrid perpetuals. These, the most popular of all roses, should be pruned annually to keep them blooming well. The more vigorous varieties like 'Peace' should, however, be pruned lightly or they will produce lots of leaves and few flowers.
Floribundas. Generally, moderate pruning is in order, but the best method is to prune some growth lightly, other growth severely. This produces both an earlier and a longer display of blossoms.
Miniatures. It's best not to prune miniature roses back too much when you plant them. If they send up strong shoots that make their shape unbalanced, remove these shoots at their point of origin.
Polyanthas. These roses tend to be twiggy and produce much dead wood. Be sure to keep their centers open.
Climbing hybrid teas and floribundas. Little pruning is required. Simply remove dead or worn-out canes and stems that have flowered.
Ramblers. They blossom best from short laterals sprouting from long, unbranched canes produced the previous year. You can distinguish a true rambler from other climbing roses by the many new shoots that sprout from the base while the plant is in full bloom. Never cut these away. They are the canes that will bloom next year. Prune ramblers in August, cutting the old canes that have flowered to the base.
Pillar roses. Unlike most climbing roses, pillars grow and flower upright. (Most climbers only flower well when trained horizontally.) In autumn, remove worn-out canes whose bark has grown rough and dark and whose laterals are producing weak, twiggy growth. Also cut back one or two of the new canes by about two thirds of their length. In summer remove spent flowers.
Species and shrub roses. They require little pruning, but "little" does not mean none. During the winter tip back all vigorous canes and laterals to encourage abundant flowering. If the bush becomes overcrowded, remove one or two of the oldest canes. Regularly remove spent flowers.
Rose hedges. Floribundas are usually used in rose hedges, which can be pruned as you would any hedge. Do not cut back more than one third of the hedge.
Standards. These, usually formed from hybrid tea or grandiflora roses, can be pruned back by about half to keep the head compact. Remove any shoots growing from the trunk below the head.