We continue to get questions here at the Extension office on caring for Knock Out roses for the winter. These landscape or shrub roses really need no special care for winter. No need to mulch like with hybrid tea roses as they are grown on their own roots. So even if they winter kill to the ground they come back true.
Knock Out Rose
As for pruning they are best pruned or cut back in the late winter or early spring. Late March through mid-April is the ideal time.
If you have hybrid tea roses or other grafted roses now is the time to mulch for the winter. Protect the graft with a mound of garden soil 6 to 8 inches high over the center of the plant. This will be removed in early April.
Dennis - Johnson County Extension