viscosum AGM

Rhododendron viscosum

Subgenus Pentanthera Section Pentanthera

Species deciduous azalea

Synonym: The Swamp Azalea

Epithet: Sticky

AGM 1937 (1993, 2002) 2012


An upright deciduous shrub usually to 1.5-2m high in cultivation, but can be a small tree to 4.5m in the wild

Flowers: Trusses of 3-14 tubular funnel shaped, single flowers, opening after the leaves. Flowers are 30-45mm long × 15-25mm wide; white or white shaded pink


Scented with a strong spicy fragrance

Foliage: Dark green leaves with a paler green underside; obovate, oblong-obovate or oblanceolate; 15-73mm long × 5-35mm wide; leaves usually glabrous, margin strigose; midrib strigose. Deciduous

Distribution: Maine, Massachusetts, Connecticut to N Carolina, parts of S Carolina, SE Tennessee, Ohio and Louisiana

Other Information: introduced in 1734 by Bartram; a variable species often called Swamp Honeysuckle. A species azalea which grows well in wet but not stagnant soils with some sun; commercially available

Number 65 of the Top 100 Rhododendrons chosen by members of the RCM Group in 2015

R. viscosum var. glaucum the leaves on this form are glaucous below and sometimes both surfaces

AM 1921 (F.G. Strover) as Azalea viscosa glauca; flowers white

R. viscosum var. rhodanthum is the usual pink form of this species

Location and Photo: Caerhays Estate

Location: Surrey

Photo: Polly Cooke

Location: Tannersville Bog,PA
Photo: Philippe de Spoelberch

Location: Surrey

Photo: Polly Cooke

Photo: John Weagle

Photo: John Weagle

Photo: Hans Eiberg