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TREES & plants

Butterfly Bush

Butterfly bush in full flower.

A long-blooming shrub or woody perennial with dense clusters of fragrant flowers, butterfly bush attracts butterflies and hummingbirds. Often considered a sub-shrub because it dies back to the ground. A great addition to sunny borders and dry open gardens. 

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


Botanical name: 
Buddleja davidii (syn Buddleia davidii)
All Common Names: 
Butterfly bush, Summer lilac
Family (English): 
Family (Botanic): 
Tree or Plant Type: 
  • Perennial
  • Shrub
Native Locale: 
  • Non-native
Landscape Uses: 
  • Specimen
  • Massing
  • Foundation
  • Mixed border
  • Patio/sidewalk
Size Range: 
  • Large shrub (more than 8 feet)
  • Medium shrub (5-8 feet)
Light Exposure: 
  • Full sun (6 hrs direct light daily)
Hardiness Zones: 
  • Zone 5
  • Zone 6
  • Zone 7
  • Zone 8
  • Zone 9
Soil Preference: 
  • Dry soil
  • Moist, well-drained soil
  • Deciduous (seasonally loses leaves)
Season of Interest: 
  • Mid summer
  • Late summer
Flower Color & Fragrance: 
  • Fragrant
  • Blue
  • Pink
  • Purple
  • White
Shape or Form: 
  • Arching
  • Multi-stemmed
  • Spreading
  • Upright
Growth Rate: 
  • Fast
More Information: 

Tree & Plant Care

A medium shrub or wooody perennial, grows 6 to 8 feet high and 5 to 8 feet wide.
A butterfly magnet with long season of blooms. Regular dead-heading will promote new blooms.
Late to leaf out in spring.
Thrives in full sun, requires well-drained, humus rich soil.
Will die back to ground in winter, prune in early spring to promote vigorous new growth and flowering.

Disease, pests and problems

Mites, cold, wet soil can cause root rots

Disease, pest, and problem resistance

Tolerant of heat, humidity, drought, and poor soils as long as they are well-drained.

Native geographic location and habitat

Native to China.

Attracts birds & butterflies

This plant is a nectar source, attracting the monarch, buckeye, black swallowtail, pipevine swallowtail, snout butterfly, great spangled fritillary, pear crescent, red admiral, painted lady, common checkered-skipper, and nymphalid butterflies.

Leaf or needle arrangement, size, shape, and texture

Simple, opposite leaves; lance-shaped, 4 to 6 inches long
Blue-green to silver-gray; no real fall color

Flower arrangement, shape, and size

Small flowers in long, upright terminal clusters.
Flowers on new wood.
Color varies with cultivar from white, pink, purple to deep blue.

Fruit, cone, nut, and seed descriptions

Two-valved brown capsule; not ornamentally important.

Cultivars and their differences 

Black Knight (Buddleja davidii 'Black Knight'):  Dark purple flowers in terminal spikes in June through September.

Blue Chip (Buddleia 'Blue Chip'):  2 to 3 feet high and wide;  small, compact miniature with continuous bluish-purple flowers, excellent for containers.  Part of the Lo & Behold® series

Ice Chip (Buddleia 'Ice Chip'):  18 to 24 inches high and 2 to 3 feet wide; low-spreading ground cover with white flowers