Question:
I planted Primroses last fall, and they look great except for one issue. The flower clusters are stretching and flopping over instead of staying above the foliage. What can I do to fix this?Answer:
- This issue is common with the Pacific Giant Hybrid variety of English Primrose because it reacts to changes in day length.
- As days become longer, the stem supporting the flower cluster stretches and can topple over when it becomes top-heavy. Moisture buildup in the florets and wind make the problem worse.
- Unfortunately, little can be done to prevent this, but planting the ‘Acaulis’ or dwarf variety of primrose can avoid it.
- They are available starting in January and not in the fall. Dwarf Primrose does not bloom in warm to mild temperatures, so our fall temperatures are too warm for flowering.
- Also, unlike the Pacific Giant Hybrids, the ‘Acaulis’ varieties do not produce flowers clustered on a single stem; instead, each flower grows on its own stem.
- Additionally, these stems do not stretch over time. They’re day length neutral, meaning the flowers stay just above the foliage and never grow taller.
- They grow four to eight inches tall and six to eight inches wide, with a wide range of colors. One downside is that in prolonged wet conditions, they can develop a gray fuzzy mold called Botrytis. Fungicides can be used, but keeping conditions dry is the best way to prevent this disease.
Question:
Many years ago, we planted a climbing rose on the south side of the house. It has been somewhat neglected, so it has grown two stories high, become very woody, and doesn’t bloom on the lower half. Can I prune it heavily to turn it into a bush, and when is the best time to do so?Answer:
- Sure, you can prune climbing roses quite heavily, just like bush roses. Their main pruning season runs from now through the end of March.
- The first step I recommend is to cut back the rose using a pruning saw or chainsaw at any height you prefer; how about four feet off the ground? Then, wait for new growth to appear before finishing the shaping. This can be done in late February or March.
- Before pruning a climbing rose, try to identify whether it is a Hybrid Tea, Grandiflora, or Floribunda. The flowers on Hybrid Teas and Grandiflora bloom on second-year wood, so heavy pruning might prevent blooming next year.
- However, in your case, reducing height takes priority over flowering. Floribunda climbers bloom on first-year wood, so heavy pruning usually won’t affect them as much. Hybrid Teas and Grandiflora roses tend to have larger flowers, while Floribunda flowers are smaller, about the size of a fifty-cent piece.
- If you're unsure, consider not pruning and instead planting another climber at the base to fill the gap. Another option is to plant a new variety at the base and let it grow up into the existing rose. Newer climbing rose varieties are advantageous because they bloom on both old and new wood, so you don’t need to be as cautious when pruning.