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TREES & plants

Bluebeard

A mounded woody plant with cornflower-blue flowers in late summer and fragrant, silvery-green foliage.  Though bluebeard is technically a shrub, it should be treated as a perennial in the Midwest because it tends to die back in harsh winters.

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

 

Botanical name: 
Caryopteris x clandonensis
All Common Names: 
Bluebeard
Family (English): 
Verbenaceae
Family (Botanic): 
Vervain
Tree or Plant Type: 
  • Perennial
  • Shrub
Native Locale: 
  • Non-native
Landscape Uses: 
  • Massing
  • Hedge
  • Foundation
  • Mixed border
  • Patio/sidewalk
Size Range: 
  • Small shrub (3-5 feet)
  • Low-growing shrub (under 3 feet)
Light Exposure: 
  • Full sun (6 hrs direct light daily)
  • Partial sun/shade (4-6 hrs light daily)
Hardiness Zones: 
  • Zone 5
  • Zone 6
  • Zone 7
  • Zone 8
  • Zone 9
Soil Preference: 
  • Alkaline soil
  • Moist, well-drained soil
Foliage: 
  • Deciduous (seasonally loses leaves)
Season of Interest: 
  • Early winter
  • Mid winter
  • Late summer
  • Early fall
  • Mid fall
  • Late fall
Flower Color & Fragrance: 
  • Fragrant
  • Blue
Shape or Form: 
  • Mounded
  • Round
Growth Rate: 
  • Moderate
  • Fast
More Information: 

Tree & Plant Care

Though it is technically a shrub, the plant should be treated as a perennial; dieback can occur in harsh winters.
Grown for its late summer blue flowers, plants reach 2 to 3 feet high and wide.
Do not cut back in fall; spring pruning promotes new growth and flowers. Cut back in early spring. 
Best in full sun in well drained soil. Can die back in winter in wet, clay soils.
Best planted in groups for bigger flowering impact.

Disease, pests and problems

No serious problems
Root rot may occur in poorly drained sites.

Native geographic location and habitat

Of hybrid origin

Attracts birds & butterflies

Flowers attract butterflies and hummingbirds.

Leaf or needle arrangement, size, shape, and texture

Simple, opposite leaves;  lance-shaped, 1 to 2 inches long; margins can be entire to finely toothed
Blue-grey with silvery undersides; fall color is a buttery yellow
.

Bluebeard (Caryopteris x clandonensis)Bluebeard (Caryopteris x clandonensis)photo: John Hagstrom

Flower arrangement, shape, and size

Cornflower blue flowers borne in clusters (cymes) from the axils of the stem in late summer

Fruit, cone, nut, and seed descriptions

Clusters of tan capsules; ornamentally interesting in winter.

Cultivars and their differences 

Blue Mist (Caryopteris x clandonensis 'Blue Mist'):  powder blue flowers

Dark Knight (Caryopteris x clandonensis 'Dark Knight'):  An upright habit grows 3 to 4 feet high and 2-3 feet wide, rich deep blue flowers

Longwood Blue (Caryopteris x clandonensis 'Longwood Blue'): a taller cultivar reaching a height of 3 to 4 feet high,  violet-blue flowers

Petit Bleu™ (Caryopteris x clandonensis 'Minblue'): compact 24 to 30 inch tall with deep blue flowers