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 in early spring (after the last hard frost of the year). In general, if you cut your Knock Out® Rose back in early spring, it will triple in size by the end of the season (cutting back to 12” high should yield a plant that is about 3’ tall by the end of the season).
Follow these simple steps to cut back your Knock Out® Roses:
1: Gather your Tools
You will need a few basic tools when the time comes to cut back your roses: gloves, hedge shears, and hand pruners.
2: Decide where to Cut
Determining where to cut depends on what size you want your rose bush to finish. Your Knock Out® Rose will usually triple in size after cutting it back to about 12” tall, so you can expect it to grow to about 3’ by the end of the season.
3: Trim out Smaller Canes
After you cut back, check your rose bush for any smaller or damaged canes that may need to be removed to promote better growth and air flow in between branches. Remove these with your hand pruners.
4: Discard the Debris
Once you have finished, be sure to gather and discard the debris.