Noteworthy Characteristics
Rhododendron catawbiense, commonly called Catawba rhododendron or mountain rosebay, is a large, rounded to spreading, multi-stemmed, broadleaf evergreen shrub that typically grows to 6-10’ (rarely to 20’) tall. It is native to the eastern U.S. from Maryland to Kentucky south to Alabama and Georgia, with concentrations in alpine woodlands, rocky slopes and ridges in the Appalachian Mountains from Virginia to Georgia where it often forms dense thickets. Alternate, elliptic to oblong, glossy, dark green leaves (to 3-6” long). Funnel-shaped lavender-pink flowers have green to yellow-brown throat markings. Flowers bloom mid to late spring in compact showy terminal clusters (trusses), each containing 15-20 flowers. Flowers are followed by elongated dry seed capsules (each to 1/2 to 1” long) which mature in fall. Gray-brown bark develops fine scales with age. Provides shelter and nesting sites for birds and wildlife. Flowers are a nectar source for butterflies. This shrub is an important parent of a large number of frost-hardy hybrids.
Genus name comes from the Greek words rhodo meaning rose and dendron meaning tree. Transferred from the Greek name for Nerium oleander.
Specific epithet comes from the Catawba region of the Blue Ridge Mountains of eastern North America.
‘Roseum Superbum’ is an open, multi-stemmed evergreen rhododendron that typically grows to a mature height of 8 ft tall and 7 ft wide. It has large, narrow, leathery medium-green leaves and features large trusses of flowers that range from lavender to pink with gold blotches.
Problems
Rhododendrons are susceptible to many insect and disease problems, including but not limited to canker, crown rot, root rot, leaf spot, rust, powdery mildew, aphids, borers, lacebugs, leafhoppers, mealybugs, mites, nematodes, scale, thrips and whiteflies. A healthy plant in the proper environment should have limited problems.
Uses
Shrub borders. Woodland gardens. Shady locations. Naturalized areas. Wood margins. Accent/specimen, groups or mass plantings.