When should I prune my knockout roses? Some already have new growth.
Marshall County Kentucky
See below for more detail on how.
Remove all dead wood and any canes that are diseased, broken,
or injured in any way. Prune to improve the shape of the plant and to permit air movement throughit by removing branches that
cross through the center of the plant or rub other branches. Also remove suckers from the rootstock and thin, weak growth. Gener-
ally, pruning back to one or two outward-facing buds or branches per cane encourages growth to the outside and creates an open, vase- shaped bush. It also allows good air circulation to reduce fungal dis- eases. Do not prune healthy shoots of climbers until after owering.
All cuts should be clean and smooth, so make sure the pruning shears are sharp. Place a drop of white glue (e.g., Elmer’s) on top of each cut stem that is larger than one-quarter of an inch. Glue helps reduce borer infestation into the cane.
Additional Summer Pruning
Continue pruning during the growing season to remove spindly shoots, suckers, diseased stems, insect-ridden areas, and other types of worthless wood. Summer pruning is as important as initial spring pruning.
Prune climbers after bloom. Remove one or two old canes, thin dense growth, and cut back remaining canes to keep the plant within bounds.
Please let me know if you have questions.
Ps: check out our rose pub for even more information at:http://www2.ca.uky.edu/agcomm/pubs/id/id118/id118.pdf