Lady Bird Johnson Wildflower Center - The University of Texas at Austin information

 Native Plant Database

Clethra alnifolia

Coastal pepperbush, Coastal sweet pepperbush, Coastal sweet pepper, Alderleaf pepperbush, Alderleaf clethra, Clethra, Summer sweet

Clethraceae (Sweet-Pepperbush Family)

Clethra alnifolia (Coastal pepperbush)
Vick, Albert F. W.
Coastal sweet-pepper or summer sweet is a narrow, 6-12 ft., deciduous shrub, which often spreads into mounded clumps. A tall, many-branched, leafy shrub with spike-like, upright clusters of fragrant white flowers. The shrub has erect, multiple stems; exfoliating bark; and simple, oval, toothed leaves which turn dull yellow to orange in fall. The dense, narrow, cylindric flower spikes are often clustered together at branch ends. Fragrant flowers are white and are followed by brown capsules which persist through winter.

This shrub forms sizable patches and is remarkably free of any disease, insect, or physiological problems. Its dry fruiting capsules remain long after flowering and help identify this plant in winter. Mountain Pepperbush (C. acuminata) has more pointed leaves and is found in southern mountains.

Image Gallery:

17 photo(s) available

Plant Characteristics

Duration: Perennial
Habit: Shrub
Leaf Retention: Deciduous
Leaf Arrangement: Alternate
Leaf Complexity: Simple
Leaf Venation: Pinnate
Leaf Margin: Serrate
Breeding System: Flowers Bisexual
Inflorescence: Spike
Size Notes: Normally 3 to 6 ft, but can reach 12 ft.
Leaf: Green, turning pale gold in fall. New growth bronzy.
Autumn Foliage: yes
Flower: Flowers in 3 to 8 inch spikes
Fruit: Brown
Size Class: 3-6 ft. , 6-12 ft.

Bloom Information

Bloom Color: White , Pink
Bloom Time: Jul , Aug
Bloom Notes: Blooms on new growth


USA: AL , CT , DE , FL , GA , LA , ME , MD , MA , MS , NH , NJ , NY , NC , PA , RI , SC , TN , TX , VA
Canada: NS
Native Distribution: MS to FL, n. through eastern portions of the coastal states to s. ME; also locally in LA & TX
Native Habitat: Swamps; sea shores; stream banks; hillside bogs

Growing Conditions

Water Use: High
Light Requirement: Sun , Part Shade , Shade
Soil Moisture: Wet , Moist
Soil pH: Acidic (pH<6.8)
CaCO3 Tolerance: Low
Drought Tolerance: Low
Soil Description: Many wet to moist, acid soils, including sands and clays.
Conditions Comments: Excellent for coastal gardens due to salt-spray tolerance.


Use Ornamental: Fragrant, showy summer flowers. Outstanding fall color.
Use Wildlife: Bees, butterflies, and hummingbirds use flowers. Many birds and mammals eat the fruit.
Conspicuous Flowers: yes
Fragrant Flowers: yes
Interesting Foliage: yes
Attracts: Birds , Hummingbirds , Butterflies

Last Update: 2015-09-30