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Shrub rose hybrids

Double Knockout rose in flower.

Shrub roses are one of the most reliable and popular roses available.  They are long blooming, come in many colors, low maintenance and feature good resistance to disease. The Knockout® series and the Carefree™ series withstand hot, humid summers and cold winters of the Midwest.

This plant has some cultivated varieties. Go to list of cultivars.

 

Botanical name:

Rosa hybrids

All Common Names:

Hybrid shrub rose, Knock out rose, Carefree rose

Family (English):

Rose

Family (Botanic):

Rosaceae

Tree or Plant Type:

  • Shrub

Foliage:

  • Deciduous (seasonally loses leaves)

Native Locale:

  • Non-native

Landscape Uses:

  • Container,
  • Foundation,
  • Massing,
  • Mixed border,
  • Patio/sidewalk,
  • Specimen

Size Range:

  • Small shrub (3-5 feet)

Light Exposure:

  • Full sun (6 hrs direct light daily),
  • Partial sun/shade (4-6 hrs light daily)

Hardiness Zones:

  • Zone 5 (Chicago),
  • Zone 6,
  • Zone 7,
  • Zone 8,
  • Zone 9

Soil Preference:

  • Moist, well-drained soil

Tolerances:

  • Occasional drought

Season of Interest:

  • Mid summer,
  • Late summer,
  • Early fall

Flower Color & Fragrance:

  • Fragrant,
  • Pink,
  • Red

Shape or Form:

  • Irregular,
  • Round

Growth Rate:

  • Slow,
  • Moderate

More Information:

Size & Form

Rounded to irregular form
Carefree™ roses reach 4 to 5 feet high and 2 to 4 feet wide
Knockout® series reach 3 to 4 feet high and wide

Tree & Plant Care

Best in full sun with at least 6 hours for maximum flowering, will tolerate part shade with reduced flowers.
Requires well drained soil.
Grows on its own roots. Should be planted at the same level they are in the pot, or slightly deeper.
Drought tolerant once established.

Prune slightly in early spring to remove dead canes and promote new growth.
Site plants for good air circulation to prevent diseases.
Shrub roses do not require winter protection.

Disease, pests, and problems

Powdery mildew in wet weather.
Rose slug sawfly, Japanese beetles, and plume moth

Disease, pest, and problem resistance

Resistant to black spot

Native geographic location and habitat

Of hybrid origin. 

Leaf or needle arrangement, size, shape, and texture

Alternate, compound leaves emerge purplish-red, turn to dark green in summer then turn a purplish-burgundy in fall.
Leaves are semi-glossy with slightly serrated margins.

Flower arrangement, shape, and size

Knock Out® roses produce lightly fragrant flushes of blooms every five to six weeks from late spring to the first hard frost. 
Carefree™ roses are long blooming and fragrant.
Flowers can be single or double depending upon cultivar.
Self-cleaning, flowers fall off once they fade. 

Fruit, cone, nut, and seed descriptions

Rose hips can be red to orange and usually develop late fall if plants are left unpruned to encourage dormancy.

Cultivars and their differences 

 Knock Out® series

Knock Out® (Rosa 'Radrazz'):  Continuous blooms of large clusters of semi-double, deep cherry-red flowers. Flowers have a light rose scent.
Bright orange-red hip in fall. Glossy leaves are burgundy-tinged, turning deep green. Black spot resistant.

Blushing Knock Out ® (Rosa 'Radyod'): A cluster of light pink, single flowers. Bloom color starts out light pink fading to soft pink. Leaves 

Double Knockout® (Rosa 'Radko'):  A double-flowering cherry-red flowering sport of original Knock Out.

Pink Knock Out® (Rosa 'Radcon'):  A double-flowering, medium pink in cool weather turning light pink in warm summer. Good resistance to black spot.

Rainbow Knock Out® (Rosa 'Radcor'): A deep, coral pink with yellow centers that do not produce a fragrance.

Sunny Knock Out® (Rosa 'Radsunny'): A more upright, compact habit. Bright yellow flowers fade to pastel cream color. Yellow more intense in cool weather.

Carefree ™ series

Carefree Beauty™ (Rosa 'Beubi'): Open habit, 3 to 4 feet high and wide; semi-double, fragrant pink flowers; thick glossy green leaves with good resistance to black spot and mildew

Carefree Celebration™ (Rosa 'Radral'): Oval to rounded 4 to 5 feet high and 2 to 3 feet wide; beautiful coral orange flowers

Carefree Sunshine (Rosa 'MEIpitac'): 4 to 5 feet high and 3 to 4 feet wide; clear yellow fragrant flowers

 

 

 

Location of Rosa hybrids (Shrub rose hybrids) at the Arboretum

We do not seem to have this in our living collection.