When does Clethra alnifolia bloom?

Clethra alnifolia blooms in July and August, producing upright spikes of small, fragrant flowers.

What pollinators does Clethra alnifolia attract?

The flower spikes are heavily visited by bees, butterflies and moths, making it a strong nectar source in mid to late summer.

How much water does summersweet need?

This shrub does best in consistently moist to wet soil and struggles in dry sites, so regular watering or a naturally damp location works well.

How much light does Clethra alnifolia need to flower well?

It flowers from full sun through fairly shady conditions, though more sun generally means denser bloom spikes.

How large does Clethra alnifolia get?

Most plants form a rounded shrub roughly three to eight feet tall and wide, often spreading slowly by suckering.

Is Summersweet toxic to livestock?

The USDA PLANTS Database does not flag Summersweet as toxic to livestock.

Is Summersweet HOA-friendly?

Summersweet is generally an HOA-friendly choice in the right placement, with moderate maintenance.

Summersweet

Name: Pollinator Patch
Author: Pollinator Patch

Clethra alnifolia

Last reviewed: September 2026

Clethra alnifolia is a deciduous shrub that flowers in July and August, sending up fragrant white spikes that attract bees, butterflies and moths in wet woodlands, pond edges and coastal thickets.

Toxicity unknown

Summersweet (Clethra alnifolia) is not listed by the ASPCA Animal Poison Control Center (opens in new tab) or the other sources we check, so we have no verdict for it either way. Absence from those lists is not a clearance. If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.

The USDA PLANTS Database (opens in new tab) does not flag Summersweet as toxic to livestock.

Light

part sun

Water

medium

Size

36"–96" H × 36"–96" W

Bloom

Jul, Aug

Native to

AL, CT, DE, FL and 17 more states

Pollinators

bees, butterflies, moths

Before you buy

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Browse plants for this ecoregion

Piedmont Northeastern Highlands Northeastern Coastal Zone Northern Forests Middle Atlantic Coastal Plain Northern Piedmont Southeastern Plains Ridge and Valley Western Allegheny Plateau Southern Coastal Plain Atlantic Coastal Pine Barrens

Summersweet is a native deciduous shrub that produces fragrant white flower spikes in mid to late summer when few other shrubs are blooming. It forms a well-behaved, rounded shape and adapts well to various soil conditions, making it reliable for landscaping. The attractive dark green foliage turns golden yellow in fall before dropping.

Growing Summersweet

Grow Summersweet in part sun and medium water. Mature plants reach 36 to 96 inches tall and spread 36 to 96 inches wide. Expect moderate maintenance to keep it looking intentional in a front yard.

In an HOA neighborhood

Summersweet is an HOA-friendly choice. Maintenance level: moderate. Tidiness: 4 out of 5.

Works well in: front yard, foundation, street edge, mid zone.

Can spread by suckers if not maintained
Winter appearance is bare but tidy

Wildlife value

The fragrant summer blooms are magnets for bees, butterflies, and moths during peak growing season. Birds also appreciate the small seeds that follow the flowers.

Common questions

When does Clethra alnifolia bloom?: Clethra alnifolia blooms in July and August, producing upright spikes of small, fragrant flowers.
What pollinators does Clethra alnifolia attract?: The flower spikes are heavily visited by bees, butterflies and moths, making it a strong nectar source in mid to late summer.
How much water does summersweet need?: This shrub does best in consistently moist to wet soil and struggles in dry sites, so regular watering or a naturally damp location works well.
How much light does Clethra alnifolia need to flower well?: It flowers from full sun through fairly shady conditions, though more sun generally means denser bloom spikes.
How large does Clethra alnifolia get?: Most plants form a rounded shrub roughly three to eight feet tall and wide, often spreading slowly by suckering.
Is Summersweet toxic to livestock?: The USDA PLANTS Database does not flag Summersweet as toxic to livestock.
Is Summersweet HOA-friendly?: Summersweet is generally an HOA-friendly choice in the right placement, with moderate maintenance.

These answers were drafted with an AI model from this plant's data. Verify care details with a local expert.

Native range data from the World Checklist of Vascular Plants (Kew). Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

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