Pruning roses seems to be one of those many mysteries of gardening.
If you have roses, you probably know they require some pruning to keep them healthy, but what does that actually look like?
As with anything, there are always differing opinions on this subject, but here is what makes the most sense to me.
Best time to prune?
Many people always prune their roses down in the fall but there are several reasons why I do not recommend that practice.
Roses have trouble going dormant in the late fall and winter, which is why you will quite often see them still blooming into December with the leaves still green.
Therefore, you should always let the last flowers of the fall remain on the plant because this signals the rose bush that it is time for them to go to sleep for the winter.
Pruning in the fall will stimulate them to keep growing into the winter and will result in more dieback on the canes. The best time to prune your roses is late dormant period-early spring just as the leaf buds are starting to swell. A good indicator of the proper pruning time is when the forsythia plants come into bloom.
How to prune roses
Regardless of the type of rose you have, the first thing to do is to cut off any dead (discoloured), diseased or damaged canes. The next step is to remove any weak canes or stems that cross through the centre of the plant or are rubbing against another cane.
Roses have alternate bud arrangement, as opposed to opposite bud arrangement where two buds are located across the stem from each other.
As I wrote about a couple weeks ago in my column on “The Science of Pruning,” all the power or energy of a plant is in the tips of each branch.
So, when you prune a branch shorter, the next bud down (the one that is now at the top) takes on the power and it will develop into a new branch. By pruning to an outward-facing bud, it controls the direction of growth to go out from the plant, instead of it growing back through the centre of it.
This helps improve air circulation, which cuts down on diseases. Make sure that you cut the stem on a 45-degree angle with the higher edge being on the side of the bud. It is important to always prune on an angle about one-quarter inch above an outward-facing bud.
The angled cut allows drops of water to roll off the top of the cane and away from the bud. Now that you have done the initial pruning of removing dead, diseased, damaged, weak and crossing canes, you now need to consider what type of rose it is.
Hybrid teas, floribundas, grandifloras, miniature and carpet roses
Once you have completed the first pruning steps noted above, you can start to prune back the remaining canes. The number of canes you will have left depends on the age and overall health of the plant.
Usually, you will have anywhere from three to eight canes and as long as those canes are healthy and the plant still has an open, symmetrical form, work with what you have.
Cut off about one-third of the original length of each cane. Hybrid tea and carpet roses can be cut back a bit further, but make sure you are leaving at least three to five buds up from the base of the plant.
The term “climbing rose” is a bit misleading as they do not climb of their own accord. The canes will not twine themselves onto a trellis and do not cling to the wall or fence.
When training a climbing rose there is one important fact to keep in mind. The vertical canes will only produce flowers at the tip of those canes. So, to get that picture-perfect image of a climbing rose that is loaded with flowers, you can carefully bend the canes and tie them to a support so that the main canes are now growing horizontally.
Instead of there being flowers just at the tip of the cane, now every bud along the horizontal cane thinks that they are at the tip and each bud will produce flowers. Once the main canes have been fanned out, prune each lateral branch (branches off the main cane) back to two or three buds.
Now your roses are trimmed up and ready for another growing season. Oh, did I mention that you may want to put on a thick pair of gloves before you begin?
Joanne Young is a Niagara-on-the-Lake garden expert and coach. See her website at joanneyoung.ca.