Sweet Pepperbush (Summersweet)

Size, growth and what to expect

Few native shrubs bloom as late as sweet pepperbush, whose fragrant white spikes 3 to 6 inches long open on the current season's growth from July into August. It grows at a medium pace, roughly a foot and a half a year in its youth on an average site, which is the rate our growth estimator uses for it. It makes a dense, upright, multi-stemmed shrub 4 to 8 feet tall and 4 to 6 feet wide that suckers into a mounded clump.

The flowers carry high-quality nectar and pollen for bees, butterflies and hummingbirds. Dry brown capsules an eighth of an inch across ripen in September and October and hang on through winter. Birds pick out the seed. Summersweet, its other name, refers to that late, sweet-scented bloom.

It grows wild along the coast from Maine to Florida and west to Texas, in swampy woods, wet marshes and damp thickets, along streams and behind the shore, often on sand.

How to grow Sweet Pepperbush

Sweet pepperbush is easy to place: full sun to fairly deep shade, ordinary garden soil or ground that stays wet, salt spray near the coast. It blooms most in sun. Plants slowly widen by suckers, so set them 4 feet apart and that far from a foundation.

Plant dormant bare-root or potted shrubs between leaf fall and bud break, in a wide, shallow hole. Set the crown at the soil line, put the native soil back in, and mulch out past the roots but not against the stems. It needs neither stake nor fertilizer. Seed is dust fine and needs no chilling. Scatter it on the surface of damp sand or seed mix in spring and press it in without covering it. Keep it constantly moist.

Water weekly through the first two summers; it wilts fast in dry soil until the roots are down. Deer browse it lightly and rabbits sometimes cut stems, so cage it low for a winter or two. It flowers on new wood, so prune in late winter, cutting the oldest stems to the ground to keep the clump full.

A lone sweet pepperbush sets some seed with its own pollen, but cross-pollinated flowers set more, so plant two or more seedlings if you want seed. Summersweet leafs out late, often not until late May, so do not write it off as dead. Spider mites trouble it in a hot, dry corner, one more reason to keep it moist. Flowers open in late July or August; leaves turn yellow in fall.