College of Agriculture, Health and Natural Resources

Plant Database

Rhododendron schlippenbachii

Royal Azalea

Ericaceae

Royal AzaleaRoyal Azalea
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Habitat

  • native to Korea, Manchuria, Japan
  • zone 4

Habit and Form

  • typical size is 5' to 7' tall; can get to 15' tall
  • a deciduous shrub
  • rounded shape
  • upright, multi-stemmed branching

Summer Foliage

  • deciduous, simple leaves
  • leaf arrangement is alternate, but appears whorled at the branch tips
  • obovate leaf shape
  • leaves 2' to 5' long
  • leaf apex is blunt or notched
  • leaves are dark green above and paler underneath

Autumn Foliage

  • a mix of yellow, orange and red
  • fall foliage is quite attractive

Flowers

  • light pink flowers
  • usually numerous and showy
  • bloom time is mid-may
  • each flower is 2.5' to 3" in diameter
  • flowers are held in groups of 3 to 6
  • fragrant

Fruit

  • non-ornamental capsules

Bark

  • gray-brown
  • not ornamentally important

Culture

  • cool, moist acidic soils are best
  • more tolerant of pH 6.5 to 7.0 than most other azaleas
  • full sun to light shade
  • avoid harsh locations

Landscape Use

  • as a specimen
  • foundation plant
  • borders
  • naturalistic areas
  • in small groupings
  • useful for flowers and fall foliage color

Liabilities

  • specific sol and site requirements
  • sometimes views as difficult to get established
  • occasional leaf spot disease

ID Features

  • very showy pink spring flowers
  • obovate leaves with blunt tips
  • orange-red fall color
  • flowers have 10 stamens

Propagation

  • by cuttings
  • by seed

Cultivars/Varieties

'Sid's Royal Pink' - This is the only commonly available form, and it is quite common in specialty catalogs. It has a more compact growth form to 5' tall with large, deep pink flowers. The fall color can be very good.

© Copyright Mark H. Brand, 1997-2015.

The digital materials (images and text) available from the UConn Plant Database are protected by copyright. Public use via the Internet for non-profit and educational purposes is permitted. Use of the materials for profit is prohibited.

Citation and Acknowledgements: University of Connecticut Plant Database, https://plantdatabase.uconn.edu/, Mark H. Brand, Department of Plant Science and Landscape Architecture, Storrs, CT 06269-4067 USA.