By Sandy Lundberg
As the end of February approaches, it will again be time to prune roses in the Lowcountry. In order to approach this job effectively, it is desirable to have an understanding of the concept of pruning. As a rose plant matures each year, it produces new canes. These newer canes are the most desirable, because they will be the most vigorous producers of flowers. Older canes may have become unproductive simply because of the aging of the plant or damage from winds and cold. Removal of these canes will allow room for new productive canes to emerge. There will also be a lot of twiggy growth that will produce inferior stems if not removed.
Exactly when should we prune? Let your rose bush and the weather channel be your guide. Generally, it is ideal to prune when the bud eyes have become red and swollen to about very small pea size. However, we remember what happened two years ago with the early March freezes. Emerging growth of several inches was frozen. For that reason, many area rosarians, including myself delay pruning. We are now waiting until the last week of February in our garden to begin pruning, depending on the weather forecasts.
As you begin, pull back the mulch to expose the bud union. Remove any small, twiggy growth, clearing out the middle of the plant. These small canes and branches left in the center are an invitation for disease and insects. Study the canes that are left. Remove any damaged or diseased canes flush with the bud union. The number of canes you leave on the plant will depend on your goals for your garden. If you exhibit and want larger, but fewer flowers, you will want to leave from 3 to 5 canes. If you want garden display, you may want to leave a few more. Now you need to determine which canes to remove. Be sure to remove the cane flush with the bud union and seal. If any are crossing or rubbing each other, remove the smallest one. If there are canes that are interfering with the plant next to it, you should remove them also. Leave last year’s new canes if they are undamaged. If any sucker growth is present, remove it also.
Cut the canes at a 45 degree angle to an outside healthy bud eye. The height depends on personal preference. If you want fewer, but larger blooms for exhibition, you will want to cut lower. Most exhibitors prune to about 18 to 20 inches. Any canes that have blackened freeze damage should be cut below the damaged area. The same is true for canes damaged by cane borers. This damage can be seen when the cane’s center (pith) is brown. Continue cutting back until healthy white pith can be seen. If you have to go back to the point where the cane is only a few inches short, it is best to remove the cane entirely. When finished, the bush should have a vase shape with the center completely open. The pruning cuts should be sealed with a sealer such as Elmer’s Glue.
In order to encourage basal breaks, you can peel off the loose layers of bark that overlay the bud union or if the bark is not loose, you may gently scrub some off with a wire brush. As long as no late freezes are expected, leave the mulch pushed back to expose the bud union. The exposure to sunshine helps encourage basal breaks.
Immediately after pruning, the bushes and surrounding ground should be sprayed with a good fungicide and a good insecticide. Thereafter it is essential that your disease and pest management program be strictly adhered to. Remove any diseased leaves that may be lying on the ground.
At this time, your organic mixture should be lightly scratched into the ground. We use 3 cups per hybrid tea and floribunda and 1 cup per miniature rose.
Pruning of floribundas follows the same principles as apply to hybrid teas with a couple of notable exceptions. Generally, floribundas that produce sprays are pruned higher and not as many canes removed. The floribundas that are noted for producing one bloom per stem, such as Sheila’s Perfume, will be pruned the same as hybrid teas.
Miniature roses are pruned with the following principle in mind. Remove the smaller, weaker canes, any twiggy growth, and any damaged canes. The number of canes left will depend on the age of the plant. Some newer minis may only have three or four good canes established, where some older plants may have as many as ten or more. Since they are on their own roots, there is not the concern to make room on a bud union for new canes. As with hybrid teas, however, the ideal is to open the middle of the plant as a disease and pest prevention measure. Usually, the height to which I prune depends on the age and thickness of the canes. About 12 to 15 inches for a large mini bush with large canes is sufficient.
Good quality tools will make this job much easier:
- Felco pruners (never use flat blade pruners as they mash the canes)
- Lobbing shears
- Pruning saw
- Thorn resistant gloves
- Elmer’s glue
- Wire brush
- A jar of alcohol (dip the pruners frequently to avoid transmitting disease)
It is a good idea to carry all of these in a plastic tote.
Note: We bought the Felco folding saw and it is great! I don’t have a lot of strength in my right wrist due to rheumatoid arthritis damage. With this saw I can easily saw through very thick canes.