Jul 21, Prune Knock Out Roses in late February, recommends the University of Georgia Cooperative Extension Service. The last hard frost typically has occurred by this time, making pruning safe, according to the rose's developer, The Conard-Pyle Company.
In the summer, prune rose bushes to remove dead or diseased branches. Make the cuts one inch below the diseased branch, so only healthy wood remains. Summer is also the time to look for any branches in the center of the bush that are growing across each other. 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 good sign that it’s time to prune.
Jan 26, Many of these roses bloom in early spring and need pruning at the end of flowering. Any new canes that have developed should be left since these will produce flowers the next stumpcutter.buzzted Reading Time: 5 mins. Jul 13, Most shrub roses are pruned in early spring with an overall trim. Buying Rose Plants. Rose plants should be purchased from reputable sources, whether through a local garden center or online. Get the best quality plants you can find- cheap, inferior rose plants will not be worth the trouble or expense of planting and care.