Blooms of the native shrub smooth hydrangea.

Native smooth hydrangea bloom. Photo: M. Talabac, University of Maryland Extension

Updated: July 12, 2022

About smooth hydrangea

Hydrangea arborescens
Deciduous shrub in the hydrangea family

Maryland distribution: common on woodland slopes, hillsides, and streambanks; rare in the coastal plain
Height: 3-5 feet high and wide
Flowers: light green to creamy white flower heads appear in June on new wood; if the spent flowers are removed, a second flush of flowers may appear in August and September; the lacecap arrangement of mostly fertile flowers in the center h a few infertile flowers around the margin 
Fall color: yellow
Sun: part shade; can tolerate full sun farther north as long as it has constant moisture; is more cold hardy than many other hydrangeas
Soil: well-drained, moist, organic, acidic soil

Garden uses: This multi-stemmed shrub has a loose habit in the wild. It can be a denser shrub with a mounded habit in cultivation. Plant in masses or groups. The foliage turns yellow before falling in autumn. It can be cut to the ground to revitalize growth, if necessary. Since it blooms on new wood, it's best to prune in late winter.

Many cultivars are available in the trade with different characteristics.  'Annabelle' is a very common cultivar with large, uniform, broad-rounded flower heads. It can spread from 4-6 feet with a height of 3-5 feet. Since this variety has sterile blooms, producing no nectar or pollen (or seeds), a fertile-flowered selection will provide better wildlife value. Several cultivars produce fertile blooms, which only have a few individual sterile flowers scattered around the outer edge of the bloom cluster, as illustrated by the photo above. This combination of fertile and sterile flowers is the typical form of wild smooth hydrangeas.

Wildlife: a nectar and pollen source for pollinators; songbirds eat the seeds; it is the host plant for the hydrangea sphinx moth caterpillar

 

The Delaware native plant garden Mt. Cuba Center evaluates selections of native plants for garden performance. You can learn more about their native hydrangea trial summary and variety recommendations in their report Wild Hydrangea for the Mid-Atlantic Region.