Karen Cambre, Sharpe, Kenneth W.
News article for September 3, 2018
Roses have regained popularity since the release of the shrub roses. Before the new varieties, rose gardeners had to devote huge blocks of time to roses and the disease issues associated with them and it was intimidating to us novice.
Prior to shrub roses most of us equated roses with the traditional hybrid tea style rose with large flowers and long growing canes.
Shrub roses, also known as landscape roses, are different and tend to grow more in a shrub fashion with flowers that grow in clusters rather than on single stems. Shrub roses do not have as many disease problems, such as powdery mildew and black spot, as the more traditional type of roses. This leads to less spraying and therefore lower maintenance with higher quality foliage.
There are a number of shrub roses on the market that perform well in our hot humid climate. A very recognizable name would be the Knockout varieties, but you may also be familiar with Home Run, Carefree and Lady Elise May.
Another good choice of shrub rose is Belinda’s Dream. It was selected as a Louisiana Super Plant in 2011 by university and green industry professionals and is worth taking a look at. Belinda’s Dream has medium pink flowers that are fully double with a much higher petal count than most shrub roses. This variety could be used for cut flowers. Another noted feature is that the blooms are larger and much more fragrant than most other shrub roses.
The landscape roses will go through a number of blooming cycles throughout the year. You will have a number of flushes and I have personally counted up to a hundred blooms on one mature plant at one time, impressive. You can increase the blooming frequency by cutting off the dried blooms once they are finished. This practice is known as deadheading. Use a pair of sharp pruning shears to snipe off the blooms after the bloom starts to fade.
There are different sizes of plants in the shrub roses, but my experience is that they all will get taller and wider than advertised in our climate. When Knockout roses first arrived they were supposed to get 4-5 feet tall by 4-5 feet wide. Realistically they will surpass 8 feet if they are not pruned. The older the plant and more established it is the faster they seem to grow.
Many of us are finding that our landscape roses are growing a bit out of their intended boundaries. Late August to early September is one of your two opportunities to trim back your shrub roses. The idea at this time of the year is to make some minimal cuts if needed to shape up the shrub roses and get them ready for the fall blooming cycle. You would not want to take more than one-third of the growth now. After pruning come back with a light fertilizer application. You do not want to push too hard with nitrogen as winter is coming and lots of lush growth could result in winter injury.
If you need to make significant size reductions to your shrub roses wait until winter. In late January to early February you can take off up to two-thirds of the plant material to get overgrown plants back in shape. I would not prune the roses lower than 2 feet in height.