Do Knock Out Roses Need Direct Sunlight?

About Knock Out Roses

• Bred specifically for repeated bloom and easy care, Knock Out roses require little maintenance. These plants are seldom bothered by black spot or powdery mildew, two diseases that plague most rose plants. If pruned back to 12 inches above the ground in early spring, Knock Out roses quickly reach 3 to 4 feet high and wide. Beginning in late spring, flowers appear in recurring flushes every five to six weeks, regardless of whether you deadhead or not. Knock Out roses are winter-hardy in U.S. Department of Agriculture plant zones 5 through 9 or 10, thriving throughout Florida and other hot and humid areas.

Knock Out Rose Varieties

• As of 2011, there are seven varieties of Knock Out roses, many of them award winners. The original Knock Out rose (Rosa 'Radrazz') has reddish-pink, loosely doubled flowers and dark green foliage. The Double Knock Out Rose (R. 'Radtko') is fully double and clear red. The Pink Knock Out rose (R. 'Radcon') is a bright pink, single rose. The Pink Double Knock Out rose (R. 'Radtkopink') is fully double and bright, bubble-gum pink. Rainbow Knock Out roses (R. 'Radcor') have single, coral pink flowers with yellow centers. The Blushing Knock Out rose (R. 'Radyod') has light pink, single flowers that fade as they age. Finally, the Sunny Knock Out rose (R. 'Radsunny') is unique in several ways -- it's the only yellow Knock Out rose, it grows up to 5 feet tall and it has a light tea-rose fragrance. All Knock Out roses are patented and cannot be vegetatively propagated in any way by home gardeners.

Care and Feeding

• Knock Out roses bloom on new wood and should be pruned back to 12 inches above the ground in early spring. If you live in an area with a long gardening season, feel free to cut the shrub back during the summer to control its size, but prune immediately after a flowering cycle so you don't delay reblooming. Conard-Pyle recommends feeding the roses once per year, right after the first flush of flowers fade. Use a balanced rose fertilizer and always apply the fertilizer to moist soil. Knock Out roses grow best in soil with a neutral pH, around 7.0.

Direct Sun Requirements

• Knock Out roses do indeed need direct sun to thrive. All varieties of Knock Out roses need at least six hours of sunlight to bloom well, and the more sunshine, the better. If you want to try planting them in a partially shaded location, site them where they'll get morning sun and afternoon shade. That location allows the foliage to dry off quickly in the morning, reducing the likelihood of fungal diseases such as black spot and powdery mildew that occur more often in shaded areas.