Red Knock Out Rose

Light Needs

Full Sun

(6+ Hours Direct Sun)

Mature Height

4-5 Feet

Mature Spread

4-5 Feet

Growing Zones

5 to 11

Red Knock Out Rose is the original award-winning Knock Out variety that revolutionized rose gardening. Rosa 'Radrazz' produces cherry red to hot pink blooms in steady cycles from late spring until hard frost. The bushy plant averages 3 to 4 feet tall and wide, with deep purplish green foliage that shifts toward burgundy in fall. Our landscaper uses it in sunny hedges and foundation beds when customers want months of color from a rose that can handle regular landscape conditions.

This Will Radler introduction set a new standard for disease resistance in landscape roses. Red Knock Out Rose is black spot resistant, drought tolerant once established, and self-cleaning, so spent flowers do not need constant removal. It has earned major recognition, including All-America Rose Selections honors, the ADR Award in Germany, and induction into the World Federation of Rose Societies Rose Hall of Fame. Plant it as a specimen, flowering hedge, mass planting, mixed-border shrub, cottage garden rose, or long-blooming accent near walkways and patios.

Red Knock Out Rose Care

Plant Red Knock Out Rose in full sun for the heaviest flowering, though it can bloom in part shade if it receives several hours of direct light. It grows best in slightly acidic, moist, well-drained garden loam enriched with compost. Avoid soggy soil and tight planting sites where air movement is limited.

Water deeply after planting and keep the soil evenly moist while roots establish. Established plants tolerate dry periods, but morning watering during summer heat keeps the bloom cycle more consistent and helps foliage dry before evening. Fertilize in early spring with a rose fertilizer, and feed lightly after major bloom cycles if the plant is actively growing. Mulch in summer to cool the roots, conserve moisture, and reduce weed pressure.

Prune Red Knock Out Rose in late winter to early spring as new growth begins. Remove dead, damaged, or crossing canes. Reduce the shrub by about one-third to refresh the plant and encourage branching. Deadheading is not required, but a light trim after a heavy bloom cycle can keep hedges looking even.

Red Knock Out Rose Spacing

Space Red Knock Out Rose 3 to 4 feet apart for a hedge or continuous mass planting. For individual shrubs, provide 4 feet of room in mixed borders so air can move around the foliage. For containers, use a pot at least 18 to 22 inches wide with drainage holes, and keep moisture steady during hot weather.

For a sunny rose border, plant Red Knock Out Rose with agastache, coneflower, and yarrow to extend flower interest and attract pollinators in the same bright, well-drained conditions. Distylium can add an evergreen backdrop, especially when the rose will be cut back in early spring. In containers, use zinnia or fan flower around the edge for seasonal color that likes full sun and regular watering.

Red Knock Out Rose Information

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