Rhododendron kaempferi ( Double Beauty Kaempferi Hybrid Azalea )
Rhododendron kaempferi , or flannel mullein azalea , is a cold - audacious , semi - evergreen bush , usually tall and broad . The Kaempferi cross were bred from R. kaempferi as well as R. ‘ Malvatica ’ and R. “ Maxwelli . ’ leave are calendered , lance - shaped to ovate , 1 1/2 to 2 inch long . Flowers are borne in showy trusses of 2 to 4 per cluster ....