Wednesday, January 13, 2010

Rose pruning in Los Angeles

It’s that time of year again in Los Angeles for all of us rose enthusiasts. Yes it’s time for our annual winter/spring rose pruning.

The pruning of rose bushes can be confusing, especially when you start talking about hybrid teas, old garden roses, shrub roses, once-blooming roses, and English roses.

The class of rose and the time of year it blooms influence the type and amount of pruning. General pruning principles apply to all roses, but there are differences between classes. The closer one gets to species roses the less severe the pruning. Hybrid teas have the distinction of requiring the most severe pruning for optimum bloom and plant health.

Because of the variety of rose types available, one may need to have an understanding of how the rose flowers. Pruning should also be looked at as applying a few common sense principles to accomplish several tasks. These tasks are to remove dead, damaged, or diseased wood; increase air circulation; keep the shrub from becoming a tangled mess; shape the plant; and encourage the growth of flowering wood. Always prune above a bud that faces outward on the plant. That way, when the plant re-sprouts, it will grow outward. This improves air circulation throughout the plant, which decreases the occurance of blackspot and other fungal diseases.

Always remove old or diseased canes at the bottom of the plant. (Rose stems are called canes.)
Remove crossing stems from within the plant. They will either rub together, opening a spot for disease to enter the plant, or will grow together, making future pruning difficult.

What some people don’t realize is that different types of roses require different types of pruning. While hybrid tea roses benefit from a hard cut leaving just a hard wood fan, many heirloom roses need much less branch cutback and really only require a general thinning and shape. Here are some examples of how certain varieties should be pruned for winter/spring growth.

Hybrid teas

Start by cutting all old rose canes to the ground.
Move on and shorten the entire shrub by 1/3.
Next, remove any crossing branches.
Make sure you prune to an outward-facing bud. This is especially important with the teas.

Repeat-flowering shrub roses bear flowers on mature stems that are not old and woody. Severe pruning of these roses would result in reduced flower production. In their first two or three seasons in the garden, shrub roses can be left unpruned. Wait to see what shape develops and then try to prune so that the shape is maintained. Many modern shrub roses are pruned by a method called the "one-third" method. Suggested pruning sequence:
In the spring, remove one-third of the very oldest canes. This helps keep the plant from becoming an overgrown thicket of poor-flowering canes.
Replace these canes by identifying about one-third of the very youngest canes that grew the previous season.
Remove the remaining canes.

Rose climbers and ramblers
Climbers and ramblers may need a few seasons in the garden before pruning is necessary. In many cases, pruning is limited to removing winter-damaged wood. Pruning is similar for both classes. The difference is in the timing. Because ramblers are once-blooming, they are pruned right after flowering in early summer. Because climbers are repeat bloomers, they are pruned in early spring. Reducing the side shoots or laterals to 3-6 inches stimulates flower production, resulting in more blooms. Training canes to grow more horizontally encourages the growth of bloom producing side shoots.

Old Garden roses such as roses, alba, gallica, bourbon, centifolia, damask,eglantine, moss , noisette etc
These roses are pruned much like modern shrub roses with some important considerations based on class. Old once-blooming roses such as Alba, Gallica, Centifolia, Damasks, and Mosses produce flowers on old wood, all pruning should be delayed until after flowering. Then, you do as little or as much pruning as is required to maintain the plant. Thinning and removing old wood is encouraged. These roses may not need annual pruning if there is no dead or damaged wood present.

Last but certainly not least, always prune about 1/4" above an outward facing leaf which has five leaflets. See below to note difference between the three leaflet and five leaflet leaf.

Environmental Concept provides earth-friendly landscape services to fine residences and commercial properties in Los Angeles, California. Tania Gybels brought her unique perspective to the world of Los Angeles horticulture in 1991. Her work has been featured on HGTV and Oprah. For more information, please visit