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Rhododendron schlippenbachii

Common Name(s):

Phonetic Spelling
rho-doh-DEN-dron shlip-pen-BAH-kee-eye
This plant has high severity poison characteristics.
See below
Description

Royal azalea is a woody, upright, rounded, deciduous shrub in the Ericaceae (blueberry) family.  It is native to China, Japan, and Korea. Growing 6 to 8 feet tall and wide, its showy, fragrant flowers appear in April to May. The genus name derives from the Greek words rhodo, which means rose, and dendron, meaning tree.

Although royal azalea will grow in full sun, it prefers dappled sun or high open shade and moist, well-drained, acidic, humus-rich soil. It does not tolerate dense clay, so if you have clay soil, amend with organic material. The roots may rot if soil does not drain well. Plant the root ball high in the soil to help with drainage issues. Pruning, if desired, may be done after flowering. 

Site this plant in a woodland or natural area. With its large size and showy flowers, it can be used as a dramatic specimen. Its flowers will also attract bees, butterflies, and other pollinators to a pollinator garden.

Insects, Diseases, and Other Plant Problems: Insect problems include aphids, borers, lace bugs, leafhoppers, mealybugs, mites, nematodes, scale, thrips, and whitefly. Diseases include canker, crown rot, root rot, leaf spot, rust, and powdery mildew. This plant tolerates browsing by rabbits but is frequently damaged by deer.

While these shrubs remain very popular for landscape use, many cultivars are susceptible to Phytophthora root rot—this leads to leaf loss, reduced vigor, branch dieback, and wilting. Implement good cultural practices first, such as improving drainage with organic matter or berms and avoiding overwatering or overfertilization. However, if you have a site with a history of this disease, consider planting one of the root rot-resistant alternative species listed in the left-hand sidebar. 

For suitable alternatives, see this video created by Charlotte Glen as part of the Plants, Pests, and Pathogens series.

VIDEO Created by Elizabeth Meyer for "Trees, Shrubs and Conifers" a plant identification course offered in partnership with Longwood Gardens.

More information on Rhododendron.

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Cultivars / Varieties:
Tags:
#showy flowers#deciduous#poisonous#fragrant flowers#houseplant#specimen#nectar plant#interiorscape#rabbit resistant#specialized bees#pollinator plant#naturalized area#problem for cats#problem for dogs#bee friendly#problem for horses#woodland garden#container plant#wildlife friendly
 
Cultivars / Varieties:
Tags:
#showy flowers#deciduous#poisonous#fragrant flowers#houseplant#specimen#nectar plant#interiorscape#rabbit resistant#specialized bees#pollinator plant#naturalized area#problem for cats#problem for dogs#bee friendly#problem for horses#woodland garden#container plant#wildlife friendly
  • Attributes:
    Genus:
    Rhododendron
    Species:
    schlippenbachii
    Family:
    Ericaceae
    Life Cycle:
    Woody
    Country Or Region Of Origin:
    China, Japan, Korea
    Wildlife Value:
    Flowers attract butterflies. Members of the genus Rhododendron support the following specialized bee: Andrena (Andrena) cornelli. This plant tolerates browsing by rabbits.
    Dimensions:
    Height: 6 ft. 0 in. - 8 ft. 0 in.
    Width: 6 ft. 0 in. - 8 ft. 0 in.
  • Whole Plant Traits:
    Plant Type:
    Houseplant
    Poisonous
    Shrub
    Woody Plant Leaf Characteristics:
    Deciduous
    Habit/Form:
    Rounded
    Maintenance:
    Low
    Texture:
    Medium
  • Cultural Conditions:
    Light:
    Full sun (6 or more hours of direct sunlight a day)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    High Organic Matter
    Loam (Silt)
    Sand
    Soil pH:
    Acid (<6.0)
    Soil Drainage:
    Good Drainage
    Moist
    Available Space To Plant:
    6-feet-12 feet
    NC Region:
    Mountains
    USDA Plant Hardiness Zone:
    4a, 4b, 5a, 5b, 6a, 6b
  • Fruit:
    Display/Harvest Time:
    Fall
    Fruit Type:
    Capsule
  • Flowers:
    Flower Color:
    Pink
    Flower Inflorescence:
    Raceme
    Flower Value To Gardener:
    Fragrant
    Showy
    Flower Bloom Time:
    Spring
    Summer
    Flower Shape:
    Funnel
    Flower Petals:
    6 petals/rays
    Flower Size:
    1-3 inches
    Flower Description:
    2 to 3 in. flowers in late spring to early summer; pale to rose pink; fragrant; open as leaves emerge
  • Leaves:
    Woody Plant Leaf Characteristics:
    Deciduous
    Leaf Color:
    Green
    Leaf Type:
    Simple
    Leaf Arrangement:
    Alternate
    Whorled
    Hairs Present:
    No
    Leaf Length:
    3-6 inches
    Leaf Description:
    Alternate, simple dark green leaves; 2 to 5.5 in. long; appears whorled
  • Stem:
    Stem Is Aromatic:
    No
  • Landscape:
    Landscape Location:
    Container
    Houseplants
    Naturalized Area
    Woodland
    Landscape Theme:
    Butterfly Garden
    Pollinator Garden
    Design Feature:
    Specimen
    Attracts:
    Butterflies
    Pollinators
    Specialized Bees
    Resistance To Challenges:
    Rabbits
    Problems:
    Poisonous to Humans
    Problem for Cats
    Problem for Dogs
    Problem for Horses
  • Poisonous to Humans:
    Poison Severity:
    High
    Poison 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.
    Poison Toxic Principle:
    Andromedotoxin
    Causes Contact Dermatitis:
    No
    Poison Part:
    Bark
    Flowers
    Fruits
    Leaves
    Roots
    Sap/Juice
    Seeds
    Stems