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TREES & plants

Buttonbush

The ball-shaped flower clusters of buttonbush.

Buttonbush is great shrub for naturalizing in wet areas. The glossy green leaves and fragrant, round flower clusters during mid-summer attract butterflies.  Native to the Chicago area and the eastern United States, buttonbush attracts more than 24 species of birds, as well as numerous species of butterflies. 

"This species is native to the Chicago Region according to Swink and Wilhelm's Plants of the Chicago Region, with updates made according to current research."   

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

 

Botanical name: 
Cephalanthus occidentalis
All Common Names: 
Buttonbush
Family (English): 
Madder
Family (Botanic): 
Rubiaceae
Tree or Plant Type: 
  • Shrub
Native Locale: 
  • Chicago area
  • Illinois
  • North America
Landscape Uses: 
  • Windbreak
  • Specimen
  • Massing
Size Range: 
  • Large shrub (more than 8 feet)
  • Medium shrub (5-8 feet)
Light Exposure: 
  • Full sun (6 hrs direct light daily)
  • Partial sun/shade (4-6 hrs light daily)
Hardiness Zones: 
  • Zone 4
  • Zone 5
  • Zone 6
  • Zone 7
  • Zone 8
Soil Preference: 
  • Moist, well-drained soil
  • Wet soil
Foliage: 
  • Deciduous (seasonally loses leaves)
Ornamental Interest: 
  • Summer blossoms
  • Persistent fruit/seeds
Season of Interest: 
  • Mid summer
  • Late summer
  • Early fall
  • Mid fall
  • Late fall
Flower Color & Fragrance: 
  • Fragrant
  • White
Shape or Form: 
  • Arching
  • Irregular
  • Upright
Growth Rate: 
  • Moderate
More Information: 

Tree & Plant Care

A 6 to 12 feet high and 12 to 18 feet wide; upright arching to irregular form. Cultivars can be smaller.
Excellent for for naturalizing or wet areas; avoid dry sites.
Best in Full sun to part shade in moist to wet soils. Not tolerant of dry soil.

Long-lived. 
Prune in dormant season or early spring before new growth begins.

Disease, pests and problems

Sensitive to drought and deep shade. 

Native geographic location and habitat

C-Value: 5
Found primarily in wet  or lowland areas.

Attracts birds & butterflies

A nectar source, attracting butterflies such as the tiger swallowtail and hummingbirds.
Attracts over 24 species of birds, including robin, kingbird, and towhee.  The nutlets that persist through winter are appealing to the birds.

Bark color and texture 

Gray and somewhat peeling, develops furrows with age.

Leaf or needle arrangement, size, shape, and texture

Whorled to opposite, leaves glossy green, up to 4 inches long and 2 inches wide.
Medium green in summer turning to yellow in fall.

Leaves emerge in late spring.

Flower arrangement, shape, and size

Small, 1-inch round ball-like clusters of white flowers  held on long stems (petioles).

Fruit, cone, nut, and seed descriptions

A hard, 1-inch, ball-like fruit persist throughout winter. Reddish fall color maturing to brown.

Cultivars and their differences 

 

This plant is a cultivar of a species that is native to the Chicago Region according to Swink and Wilhelm's Plants of the Chicago Region, with updates made according to current research. Cultivars are plants produced in cultivation by selective breeding or via vegetative propagation from wild plants identified to have desirable traits."

Sputnik buttonbush (Cephalanthus occidentalis 'Bieberich'):  An 8 to 10 feet high shrub with rounded habit. Glossy green leaves turn yellow fall color.

Sugar Shack™ buttonbush (Cephalanthus occidentalis 'SMCOSS'): A short form reaching 3 to 4 feet high, fruits have reddish tipped foliage and red fruit.