I live in PA, zone 5.

Knock Out Roses Pruning Steps: To maintain a size of 3–4’ w x 3–4’ h, Knock Out Roses should be cut back once a year to 12” high. Check your rose bush from time to time in late winter/early spring, and when you start to see new shoots growing from the canes on your rose bush, that’s a Location: 8 Federal Road, Suite 6 West Grove, PA United States.

Mar 13, 1. Severe early spring pruning on one-time bloomers will sacrifice bloom. 2. Sometimes a hard cut-back will tend to restore a weak bush.

Winterizing your knockout roses should occur after the first fall freeze.

3. A bush well “shaped up” every year will be more satisfactory than a bush allowed to go rampant for several years, then cut back.

Continue reading “Suggested Pruning Techniques for Old Garden Roses”.

Mar 01, When to Prune. The beauty of Knock Out roses is that they can be pruned nearly any time without sacrificing beautiful blooms. Here in the south, we can expect the first flush of blooms around Mother’s Day in early May. This will be the largest flush of bushfalling.barted Reading Time: 4 mins.