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.
Oct 07, The main pruning period for knockout roses is in late winter or early spring, just as the plant prepares for another season of growth. X Research source You can still prune your roses even 96%. Sep 17, Prune to about a third of the desired final size. Knock Out roses typically triple in size after pruning.
Remove dead or damaged wood when you see it. Every two or three years, remove a third of old growth to rejuvenate the bushtrim.buzzted Reading Time: 5 mins.