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Clethra alnifolia 'Ruby Spice'
(Summersweet Clethra)

Devoted gardeners will recognize Clethra as an indispensable native shrub of the woodland landscape. Its beautiful white spikes of fragrant summer flowers, wet-site adaptability, and glowing yellow fall foliage have always placed this species high on the desirability list for northern gardeners.

While an impressive list of cultivars can be found in the marketplace, 'Ruby Spice' is a distinctive true pink that ranks supreme.

'Ruby Spice' was selected as a sport on a plant of 'Pink Spires' made at Broken Arrow Nursery in Connecticut. In trials at the University of Maine, 'Ruby Spice' not only had the best flower color of all 12 cultivars tested, it also had the longest flowering season.

Leaves Alternate, simple, obovate-oblong, up to four inches long and two inches wide, sharply serrate, lustrous dark green. Deciduous.

Stem Smooth brown, rounded or obscurely three-sided.

Size Will grow to eight feet high and six feet wide, and has the ability through suckering to develop into large masses where space allows.

Habit Densely leafing, erect shrub which often suckers profusely. More compact than the species.

Flowers In early to late July and into August, the plant bears bright pink blossoms on the current season's growth. The flowers are delightfully fragrant and long-lasting, up to six weeks. The blossom clusters are racemes up to six inches long that attract bees and other insects.

Culture Remarkably tolerant of a variety of conditions, including roadsides and seashores, it prefers moist locations in partial shade, but will take full sun. If necessary, prune in early spring.

Insects and Diseases No known diseases. Mite damage may occur during extremely dry years.

Hardiness Rated for Zones 4-8, although it may need some wind protection in coldest areas.

Propagation Cuttings collected in June and treated with hormone offer a high percentage of success.

Information sources: Dr. Michael Dirr, Dr. Paul Cappiello, Mark Sellew.


Produces bright yellow fall color