Some gardeners seem paralyzed with fear at the idea of pruning roses—a mindset that’s completely unwarranted: roses are tough customers that will tolerate a few gaffes as you perfect your scissor-hand technique.
The principal reason for pruning roses is to maintain their health and vigour. These plants are prone to a variety of disease and insect pests, so removing dead, diseased or damaged wood as soon as you notice it is crucial. Restricting size and reducing the number of canes (to increase light levels and air circulation) is also key: aim to create a shrub with a pleasing silhouette and well-spaced shoots that don’t cross or rub against one another.
As rose canes age they become woody and yield fewer blooms; the most floriferous canes arise from vigorous new shoots produced in spring, which will flower well the following summer. Annual pruning stimulates and encourages this kind of growth, but it’s easy to fall behind—and before you know it, your roses will begin to look miserable and neglected.
Gradual renovation over the course of two or three years will gently bring your roses back to their former glory without leaving a gap in your garden’s planting scheme.
Roses like lots of attention early on; heavy fertilizing or drastic pruning after July 1 stimulates late, lush growth that won’t harden off properly before the first frosts.
How to properly prune roses
1. With a small pruning saw, remove any dead, woody stumps at the base of the plant; otherwise, water will collect, promoting rot.
2. Using secateurs, prune any diseased or spindly canes back to their point of origin, as well as any shoots that cross.
3. Cut the oldest, woodiest stems back to a set of strong, healthy shoots that emerge close to the crown of the plant (within 30 centimetres of soil level).
4. Shorten the remaining canes so the overall height of the bush is reduced by one-half to two-thirds; stagger the height of the cuts to create new growth at several different levels.
The following spring, prune out half of the remaining oldest, thickest canes from the base of the plant; then remove the balance the next spring, by which time all the main canes will have been renewed.