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.
If you want to cut back your plant less frequently, you can certainly do so, as Petite Knock Out should maintain its height of about 18”.Missing: Watertown MA.
Oct 07, Knockout roses are a relatively low-fuss variety that can make a welcome addition to any yard or garden, but they do require a little seasonal pruning in order to grow healthy and beautiful. Cut back your roses extensively at the beginning of spring, and shape them up as needed throughout the rest of the year%. Mar 01, Remove and discard any dead, crowded, crossed or rubbing branches. The goal is to open up the plant’s center and eliminate unnecessary suckers or random shoots.
Cut the rose bush back by 1/3 to 1/2 the size.
With severe heavy pruning, the plant can be cut down to 18″″ depending on how large the rosh bush bushleaning.buzzted Reading Time: 4 mins. Sep 17, Shrub roses, including the Knock Out class, are easy to maintain. Simply give them the occasional pruning, and remove the spent bushleaning.buzzted Reading Time: 5 mins.
‘Knock Out' (red, pink, double, etc.) blooms on new growth. This means that you can prune it almost anytime you want without ruining the season's bloom. If you prune now, you'll remove some flower buds and delay flowering, but you'll get lots of blooms in a couple of bushleaning.buzzg: Watertown MA. Research indicates that Knock Out roses respond best if not cut back lower that 24 inches for the hard pruning in early spring, and more moderately in the fall.
I’m surprised they have done well cut back as short as 12 inches from the bushleaning.buzzg: Watertown MA. This two-step process keeps new growth coming and removes the hormone-filled hips that tell the rose to bloom more slowly. Remember that your Knock Out will make flowers 16 inches above where you make your summer cuts. If you want continuous blooming, clip branches 16″ below the level where you want the next flush of bushleaning.buzzg: Watertown MA.