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Rhododendron maximum

This plant has poison characteristics. See below.
Common Name(s):
Max, Rosebay rhododendron, White laurel
Cultivar(s):
Summer Glow , Red River , Summer Solace , Album , Purpureum , var. album, var. purpureum, var. roseum
Categories:
Native Plants, Poisonous Plants, Shrubs
Comment:

Rhododendron maximum, commonly called rosebay rhododendron or great laurel, is a large, upright, loose, multi-stemmed, late-blooming, evergreen shrub that is native to North America from Ontario and Nova Scotia south to Ohio, Alabama and Georgia with a concentration of plants in the southern Appalachian Mountains where it typically grows in dense thickets which dominate the understory in some locations. It typically grows to 5-15’ tall, but infrequently to 30-40’ tall in the heart of its native habitat.  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. 

The bark is thin, smooth and light brown on young trees.  As the tree ages, thin scales develop. 

Regions:  Mountain, Piedmont

Seasons of Interest: 

  Blooms:   Summer, Late summer           Nut/Fruit/Seed:  Fall

Wildlife Value:    This plant is moderately resistant to damage from deer.  It proves winter and extreme weather coverage.  Hummingbirds, butterflies, and bees are attracted to its blooms.  Members of the genus Rhododendron support the following specialized bee: Andrena (Andrena) cornelli.

Insects, Diseases, or Other Plant 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 whitefly. A healthy plant in the proper environment should have limited problems.

Height:
5-15 ft.
Foliage:
The leaves of the Rosebay Rhododendron are large, alternate, simple dark green and leathery with a smooth margin and rust covered hairs on the undersides. They can range from 4 to 8 inches long.
Flower:
Flowers (to 2” across) of the Rosebay Rhododendron are rose-purplish to pink to white, often with olive green to orange spots. Flowers bloom in umbel-like inflorescences from June to early July. Its fruit is an oblong seed capsule which splits open when ripe to release numerous seeds.
Zones:
3 to 7
Habit:
Evergreen
Site:
The Rosebay Rhododendron is winter hardy to USDA Zones 3-7 where it is best grown in acidic, humusy, organically rich, cool, moist, moisture-retentive but well-drained soils in part shade. Tolerates close to full shade. Avoid hot summer locations. Roots must never be allowed to dry out. Acidify soils prior to planting and thereafter as needed. Plant in a location protected from strong winter winds. 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.
Texture:
Smooth
Form:
Loose, open shrub
Exposure:
Sun to partial shade; moist, well drained soil
Fruit:
5 in. white flecked, blush pink with green flower trusses in summer
Family:
Ericaceae
Origin:
North America
Poison Part:
All parts of this plant are highly toxic if ingested.
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:
Andromedotoxin.
Severity:
HIGHLY TOXIC, MAY BE FATAL IF EATEN!
Found in:
Houseplant or interiorscape; landscape as cultivated woody shrub; forest or natural area.
Width:
5-12 ft.
Tags:
woodland, bees, nectar, pollinator, specialized bees, hummingbirds, wildlife, fall interest, showy, shade plant, winter interest, butterflies, evergreen

NCCES plant id: 535

Rhododendron maximum Flowers
Nancy Magnussun, CC BY-NC-2.0
Rhododendron maximum Rhododendron maximum
RockerBOO, CC BY-SA - 4.0
Rhododendron maximum In a woodland setting
Nicholas A. Tonelli, CC BY - 2.0
 Rhododendron maximum Form
RockerBOO, CC-BY-SA-2.0
 Rhododendron maximum Leaves
Raphel Medina, CC BY-NC-SA - 2.0