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Rosa hybrida 'Radrazz' PP #11836

Phonetic Spelling
RO-zuh hy-BRID-uh
Description

The Knock Out® roses are woody, deciduous shrubs in the rose family (Rosaceae). They are patented, hybrid roses bred to have a long bloom season and be particularly resistant to blackspot, a disease common to most roses. The Knock Out® trade name is now applied to more than ten cultivars, of which ‘Radrazz,’ a cherry pink single, was the first to be developed. Others include Peachy Knock Out®, Sunny Knock Out®, Coral Knock Out®, etc. ‘Radrazz’ is marketed simply as Knock Out® rose and was bred by American rose grower William Radler in 1989. 

Grow Knock Out® rose in full sun to partial shade in neutral to acidic, moist, loamy soil with good drainage. It is one of the few roses that will bloom reasonably well in partial shade. It grows to 3 feet tall and wide. It requires less pruning than most roses, needing attention only to manage the plant’s size. Lightly prune in late February. Water during periods of drought to maintain a continual supply of flowers and mulch the roots to maintain moisture and consistent soil temperatures. This rose also tolerates heat and humidity.

Knock Out® was chosen in 2000 as an All-America Rose Award winner by the American rose industry and received the American Rose Society Members Choice Award 2004. Its cherry-red single flowers have a mild tea rose fragrance and are attractive to butterflies.

Use this rose in small groups in a border, as foundation planting, or as a low hedge. Add it to a cottage, sensory, pollinator, or cutting garden.   

Insects, Diseases, and Other Plant Problems: It is susceptible to rose rosette, which is a witches broom caused by a virus that is spread through mites. It can quickly spread to other roses in the surrounding area and the only treatment is the removal of infected plants.  

VIDEO Created by Elizabeth Meyer for "Trees, Shrubs and Conifers" a plant identification course offered in partnership with Longwood Gardens.

More information on Rosa.

Profile Video:
See this plant in the following landscapes:
Flower Bonanza Garden Driveway Garden
Cultivars / Varieties:
  • 'Double Red'
  • ‘Radrazz’
'Double Red', ‘Radrazz’
Tags:
#showy flowers#fragrant flowers#heat tolerant#drought tolerant#fall flowers#specimen#red flowers#spring flowers#fall interest#cottage garden#cpp#summer flowers#border planting#cutting garden#border back#humidity tolerant#small group plantings#fall color red#fall color purple#hedge
 
Cultivars / Varieties:
  • 'Double Red'
  • ‘Radrazz’
'Double Red', ‘Radrazz’
Tags:
#showy flowers#fragrant flowers#heat tolerant#drought tolerant#fall flowers#specimen#red flowers#spring flowers#fall interest#cottage garden#cpp#summer flowers#border planting#cutting garden#border back#humidity tolerant#small group plantings#fall color red#fall color purple#hedge
  • Attributes:
    Genus:
    Rosa
    Species:
    hybrida
    Family:
    Rosaceae
    Uses (Ethnobotany):
    The fruit of rose, the rose hip, is high in vitamin C and has been used in folk medicine for stomach pain and to treat cancer.
    Life Cycle:
    Woody
    Wildlife Value:
    Butterflies and bees are attracted to the flowers.
    Particularly Resistant To (Insects/Diseases/Other Problems):
    Diseases like black spot.
    Dimensions:
    Height: 3 ft. 0 in. - 10 ft. 0 in.
    Width: 3 ft. 0 in. - 10 ft. 0 in.
  • Whole Plant Traits:
    Plant Type:
    Rose
    Shrub
    Woody Plant Leaf Characteristics:
    Deciduous
    Habit/Form:
    Erect
    Growth Rate:
    Rapid
    Maintenance:
    Medium
    Texture:
    Coarse
    Appendage:
    Prickles
  • Cultural Conditions:
    Light:
    Full sun (6 or more hours of direct sunlight a day)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    Loam (Silt)
    Soil pH:
    Acid (<6.0)
    Neutral (6.0-8.0)
    Soil Drainage:
    Good Drainage
    Moist
    Available Space To Plant:
    3 feet-6 feet
    USDA Plant Hardiness Zone:
    5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
  • Fruit:
    Fruit Color:
    Orange
    Red/Burgundy
    Display/Harvest Time:
    Fall
    Fruit Description:
    Orange-red rose hip
  • Flowers:
    Flower Color:
    Pink
    Red/Burgundy
    Flower Value To Gardener:
    Fragrant
    Good Cut
    Long Bloom Season
    Showy
    Flower Bloom Time:
    Fall
    Spring
    Summer
    Flower Petals:
    7 - 20 petals/rays
    Flower Size:
    3-6 inches
    Flower Description:
    3-inch diameter, cherry-red blooms appear as terminal clusters of single 3.5" flowers with 7+ petals on single or sometimes double flowers. Blooms appear from spring, through summer, and until the first frost of fall. Buds are ovoid and pointed.
  • Leaves:
    Woody Plant Leaf Characteristics:
    Deciduous
    Leaf Color:
    Green
    Purple/Lavender
    Deciduous Leaf Fall Color:
    Purple/Lavender
    Red/Burgundy
    Leaf Type:
    Compound (Pinnately , Bipinnately, Palmately)
    Leaf Arrangement:
    Alternate
    Leaf Margin:
    Dentate
    Hairs Present:
    No
    Leaf Description:
    Dark purple green leaves with 5-7 leaflets with toothed margins. Leaves turn burgandy-violet in the fall.
  • Stem:
    Stem Color:
    Green
    Stem Is Aromatic:
    No
  • Landscape:
    Landscape Theme:
    Butterfly Garden
    Children's Garden
    Cottage Garden
    Cutting Garden
    English Garden
    Garden for the Blind
    Pollinator Garden
    Design Feature:
    Border
    Foundation Planting
    Hedge
    Small groups
    Attracts:
    Butterflies
    Resistance To Challenges:
    Diseases
    Heat
    Humidity
    Problems:
    Spines/Thorns
    Weedy