Content Detail

Hoary bluebeard is an open, loose, woody shrub reaching 2 to 3 feet tall. It has violet-blue flowers in late summer and fragrant, silvery-green foliage. Though it is technically a shrub, it should be treated as a perennial in the Midwest because it tends to die back in harsh winters.

  • Family (English) Vervain
  • Family (botanic) Verbanaceae
  • Tree or plant type Perennial, Shrub
  • Native locale Non-native
  • Size range Low-growing shrub (under 3 feet), 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 6 (City of Chicago), Zone 7, Zone 8, Zone 9
  • Soil preference Moist, well-drained soil
  • Tolerances Occasional drought
  • Season of interest early fall, late summer
  • Flower color and fragrance Blue
  • Shape or form Mounded, Multi-stemmed, Open
  • Growth rate Fast, Moderate

Native geographic location and habitat: 

It is native to Japan, Korea, and China.

Attracts birds, pollinators, or wildlife: 

The flowers attract butterflies and hummingbirds.

Leaf or needle arrangement, size, shape, and texture: 

The opposite, lance-shaped, toothed leaves are up to 3 inches long. The foliage is dull gray with silvery undersides which adds a nice contrast to the flowers.

Flower arrangement, shape, and size: 

The violet-blue flowers are borne in clusters (cymes) from the axils of the stems in late summer.

Fruit, cone, nut, and seed descriptions: 

Tan capsules add winter interest to the shrub.

Plant care: 

Hoary bluebeard is technically a shrub, but should be treated as a perennial in the Midwest. The roots are hardy, but the stems can die back in cold winters. It is grown for its late summer flowers. It reaches 2 to 3 feet high and wide. It should be cut back in early spring to promote new growth and better flowering. It does best in full sun to part shade in well-drained soil. It will not tolerate wet clay soil.

List of pests, diseases, and tolerances: 

This plant has no serious problems, but may be subject to root rots in poorly drained sites

Sunshine Blue® Hoary Bluebird (Caryopteris incana ‘Jason’):

This cultivar is mounded and 2 to 3 feet high and wide. Bright yellow foliage contrasts nicely with its bright blue flowers.

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