Plants > All Plants > Rhododendron catawbiense

Rhododendron catawbiense

This plant has poison characteristics. See below.

Common Name(s):

Catawba rhododendron, Mountain rosebay, Purple rhododendron

Categories:

Comment:

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. Its gray-brown bark develops fine scales with age. This shrub is an important parent of a large number of frost-hardy hybrids. It will often become leggy when grown in unfavorable conditions.

Regions: Mountain, Piedmont

Seasons:

Blooms: Spring Nut/Fruit/Seed: Late summer/fall

Wildlife Value: It provides winter cover. Nectar from flowers attracts hummingbirds, butterflies, and bees.

Members of the genus Rhododendron support the following specialized bee: Andrena (Andrena) cornelli.

Insects, Diseases, and Other Plant Problems: Rhododendrons are susceptible to insect and disease problems. Insect problems include aphids, borers, lacebugs, leafhoppers, mealybugs, mites, nematodes, scale, thrips and whitefly. Diseases include canker, crown rot, root rot, leaf spot, rust, and powdery mildew. Full sun can scortch the leaves and the roots rot if soil does not drain well. A healthy plant in the right place with proper maintenance should have few problems. This plant is frequently damaged by deer.

Height:

6-10 ft.

Foliage:

The Catawba Rhododendron has large, leathery, simple, alternate, elliptic to oblong, glossy, dark green leaves (to 3-6” long) with smooth or toothed margins. It may develop yellow-green winter color.

Flower:

The Catawba Rhododendron has funnel-shaped lavender-pink flowers that have green to yellow-brown throat markings. The flowers bloom mid to late spring in compact showy terminal clusters (trusses), each containing 15-20 flowers. The flowers are followed by elongated dry seed capsules (each to 1/2 to 1” long) which mature in fall.

Zones:

4-8

Habit:

Evergreen

Site:

This plant is winter hardy to USDA Zones 4-8 where it is best grown in acidic, humusy, organically rich, evenly moist, moisture-retentive but well-drained soils in part shade. It performs well with some morning sun but needs shady afternoon conditions. It will tolerate close to full shade. Prefers cool summer temperatures. Roots must never be allowed to dry out. Acidify soils prior to planting and thereafter as needed. Plant in locations protected from strong winter winds. Do not site plants within or near the drip line of trees in the walnut family (most rhododendrons are sensitive to toxic juglones produced by roots of walnuts, butternuts, pecans and hickories). Good soil drainage is essential (doesn’t like “wet feet”). Poor drainage inevitably leads to root rot, therefore raised beds/plantings should be considered in areas with heavy clay soils. Shallow, fibrous root systems (do not cultivate around plants) will benefit greatly from a mulch (e.g., wood chips, bark or pine needles) to help retain moisture and stabilize soil temperatures. All parts of this plant are highly toxic if ingested.

Texture:

Medium to coarse

Form:

Dense, wide spreading shrub

Exposure:

Sun to high bright shade; moist, well drained soil

Fruit:

Capsule

Family:

Ericaceae

Origin:

Appalachian mountains

Distribution:

Native to southern Appalachian mountains, from Virginia through Georgia

Poison Part:

All parts.

Poison Delivery Mode:

Ingestion

Symptoms:

Salivation, watering of eyes and nose, abdominal pain, loss of energy, depression, nausea and vomiting, diarrhea, weakness, difficult breathing, progressive paralysis of arms and legs, coma.

Toxic Principle: