Clethra barbinervis

Barbinervis Clethera

Clethra barbinervis (Japanese clethra) is a refined small ornamental tree prized for its exfoliating bark, elegant branching, and four-season interest. Unlike the shrub-form summersweets, this species develops a graceful tree form and is especially valued for its smooth, mottled bark and subtle summer flowers.


Plant Profile
Type: Deciduous flowering tree

Mature Size:



Width: 15–25 ft



Height: 25–35 ft



Bloom:



Small, creamy-white flowers in loose, upright racemes



Lightly fragrant



Early to mid-summer



Foliage: Medium to dark green; turns yellow to golden bronze in fall

Bark: Smooth, exfoliating bark in shades of gray, cinnamon, and tan—excellent winter interest

Zones: 5a–8b
Light: Full sun to partial shade
Soil: Moist, well-drained, acidic soils; tolerant of clay
Water: Moderate; prefers consistent moisture but tolerates brief dry periods once established


Features & Uses


Form: Upright, rounded tree with an elegant, layered branching structure



Excellent as a specimen tree, in woodland gardens, or along garden edges



Exceptional bark interest rivals stewartia and crape myrtle



Flowers attract bees and other pollinators



Strong four-season ornamental value (bark, foliage, flowers, fall color)




Care Notes


Minimal pruning; best pruned only to remove crossing or damaged branches



Mulch to keep roots cool and conserve moisture



Performs best in slightly acidic soils

Plant type

Flowering Ornamental Tree

Height

25-35'

Width

15-25'

Hardiness zones

5–8

Sunlight

Full Sun, Partial Shade

Bloom time

Early Summer, Mid Summer

Flower color

White

Leaf color

Green

Fall color

Yellow

Attracts

Butterflies, Hummingbirds

Soil

Acidic, Clay, Moist well-drained

Landscape use

Accent Plant, Specimen

Shape

Compact Rounded

Fragrant

Yes

Drought tolerant

No