How to Care for Knock Out Roses
Knock Out roses were developed by William Radler, a Wisconsin botanist who was looking for a hardy, disease-resistant rose bush. Knock Out roses are a shrub rose bush that grows to about 3 feet in height and stays in a relatively tidy mound. Proper care will keep this rose bush blooming late into the fall.
Difficulty: Moderately Easy
Cut the Knock Out rose bush down to approximately 12 inches in early spring, using a handheld pruner.
Shape the Knock Out rose bush during the growing season. Keep the mound as rounded as possible. Trim any branches that are growing faster than others.
Remove faded blooms by deadheading to encourage new growth. Regular deadheading will keep the Knock Out rose bush blooming until late fall.
Water the Knock Out rose bush at the bottom of the shrub. Reducing the shrub's exposure to overhead watering prevents leaf spot and disease. Increase the watering frequency during dry weather.
Spread a layer of mulch around the Knock Out rose bush, taking care not to pile the mulch against the stems. Apply mulch approximately 3 inches thick.
Apply a fertilizer developed for rose bushes. Follow the manufacturer's instructions on fertilizing frequency.
Ensure that the Knock Out rose bush is in a sunny location with well-drained soil. Roses placed in heavy soil may rot.
Tips & Warnings
- Leave the Knock Out rose bush intact over the winter and cut the shrub down each spring. The roses bloom on new growth.
- Knock Out roses have thorns. Use heavy-duty gardening gloves when handling the plant.