when and how far back should you cut knockout roses
Prune the roses after the buds break dormancy. The major pruning period for knockout roses is in late winter to early spring, just as the bush begins to break out of its dormancy stage. 1  Check for bud formation on the stems of the plant. 2  You can still prune the plant even if new growth is starting to develop, though.
Knock out roses can grow up to 3-4 feet high and as wide. It seems to get to its max height in the warmer zoned climates. If the beds are 4 foot wide, and your knock outs grow to say 3 foot in width, it doesnât give you much room to plant the other upright plants. Check the width measurements given for them on the labels to see if they will fit. If they donât grow too wide, you could probably put one of them next to the roses.