 "Hymenanthes is a subgenus of the genus "Rhododendron", with a widespread distribution in the temperate Northern Hemisphere.The species are evergreen shrubs and small to medium-sized trees (up to 20 m tall), with medium-sized to large leaves (very large, over 40 cm long, in a few species).The flowers are large, produced in terminal trusses of 5-40 together.