Rhododendron yakushimanum
Common name: 
Yak Rhododendron
rho-do-DEN-dron ya-koo-shee-MAH-num
Rhododendron degronianum ssp. yakushimanum
Native to (or naturalized in) Oregon: 
  • Broadleaf evergreen shrub, 1-4 ft (0.3-1.2 m), dense, mounded.  Mature leaves 5-10 x 2.5-3 cm, linear-oblanceolate to lanceolate, stiff, leathery, tough, upper surface smooth, glossy dark green, underside has thick woolly brown hair (indumenum), new growth is covered in a white felt.  Flowers bell-shaped, 3-4 cm long and 5-6 cm wide, rich rose in the bud changing to light pink then white upon opening, about 10 per cluster.
  • - 25°F, early-mid; quality rating: 5/5/4 [flower / plant & foliage / performance; scale 1 (poor) - 5 (best)].   Sun.
  • Native to the Yaku-shima Island, Japan, also home to the conifer Cryptomeria japonica, Japanese Cedar.
  • Rhododendron yakushimanum is now more commonly classified as a subspecies of Rhododendron degronianum, that is R. degronianum ssp. yakushimanum; other subspecies are R. d. ssp. degronianum and R. d. ssp. heptamerum.
  • There are many Yak seedling clones and hybrids, a common one is ‘Ken Janeck’, which is a seedling of R. d. ssp. yakushimanum.
  • Oregon State Univ. campus: northeast of Magruder (probably a cultivar).
Click image to enlarge
  • plant habit, before flowering

    plant habit, before flowering

  • leaves


  • leaves and opening flower buds

    leaves and opening flower buds

  • plant habit, flowering

    plant habit, flowering

  • flowers


  • expanding leaves, after flowering

    expanding leaves, after flowering

  • plant habit, summer

    plant habit, summer

  • foliage


  • young leaves

    young leaves