Rose flowers are produced at the ends of secondary stems, which grow from the main cane. Though you may not think of it as such, gathering these flowers is a form of pruning. Whether you are cutting flowers for an arrangement or removing flowers that have faded (a technique known as deadheading), you follow the same rule: Cut the flower stem no shorter than just above the first five-leaflet leaf below the flower you are removing. This is the point from which the next stem will grow and, one hopes, bloom.
When removing flowers from tall and vigorous plants, you can take the opportunity to shorten and shape them. Cut the stems down as low as you want them, but leave at least two five-leaflet leaves per stem to contribute to food production. Do not remove more than 25 percent of the foliage; if you do, you will send the plant into shock and a short dormant period. First-year plants should be pruned only slightly when removing faded flowers, to encourage growth and foliage production.
Old blooms past their peak should be pruned away as soon as possible. This not only keeps the plant looking neat and the ground free of fallen petals, but also encourages the plant to send out new growth and flowers sooner.
Always remove a dead flower by taking a piece of the stem and cutting to just above a five-leaflet leaf. If you cut to a three-leaflet leaf instead, numerous small growth shoots will appear at the top of the stem but will never grow into sturdy, flower-producing stems.
To encourage repeat-blooming climbers to produce a heavy second bloom, prune and deadhead them as soon as the first flush of bloom is finished. Cut back the secondary stems, leaving two five-leaflet leaves on each. A new stem topped with a flower will grow from each leaf axil, the point where the leaf meets the stem.
Deadheading should cease as summer turns to fall since the new growth it encourages will probably not have time to produce flowers before the frost. The younger issue will also be more susceptible to damage from winter cold and wind. Leave the last roses of summer to fade naturally, and you will have plants that can better endure the rigors of winter. The only pruning that should be done in the fall is to remove any tall canes that might be damaged by the wind, or to shorten the canes enough to fit under rose cones or other winter protection.
Shrub roses, old garden roses, and climbers that bloom only once do not need to be deadheaded. After the flowers have faded, fruit known as hips will form. Rose hips can be harvested for cooking after they have ripened and turned yellow, orange, or red, or they can be left on the plant as a treat for birds.
Throughout the summer be on the lookout for suckers, which are canes that grow from the understock to which the rosebush is grafted. They are easy to recognize because they grow from below the bud union, and because their foliage is different from that of the top of the plant. If suckers ever get to the blooming stage, you will see either small white flowers or nondescript red ones, depending on the type of understock used. If suckers are not removed, they will soon overpower the plant and cause the grafted part of it to be choked out and eventually killed by the understock’s aggressive growth. As soon as you see a sucker, prune it away completely to its base.