About Rhododendron arboreum Sm.
The specific epithet of Rhododendron arboreum Sm. means "tending to be woody or growing in a tree-like form". While the species has been recorded reaching heights of 20 m (66 ft), most individuals grow to 12 m (39 ft) tall and wide. A specimen of this species holds the Guinness World Record for the World's Largest Rhododendron. This record-holding tree was discovered in 1993 on Mount Japfü in Kohima District, Nagaland, India, and measures 20 m (65 ft) tall, making it the tallest recorded rhododendron. In sharp contrast, the New Guinean epiphytic species Rhododendron caespitosum never grows taller than 4 in (10 cm). In early to mid-spring, R. arboreum produces trusses holding 15 to 20 bell-shaped flowers. Each flower is 5 cm (2 in) wide and 3 to 5 cm (1 to 2 in) long, and comes in shades of red, pink, or white, with black nectar pouches and black spots on the inside. Rhododendron arboreum is native to Pakistan, India, Nepal, Myanmar, Sri Lanka, the Himalayas, Northeast India, and Tibet, and has been introduced to Madeira. It is the national flower of Nepal. In India, it is the state tree of Uttarakhand and the state flower of Nagaland. It is also the provincial flower of Sri Lanka's Central Province. In cultivation, Rhododendron arboreum prefers moist, well-drained, leafy, humus-rich, acidic soil, and grows best in dappled shade. It has broad, dark green leaves that measure 7–19 cm (3–7.5 in) long, with a silvery, fawn, or brown hairy coating on the underside. It is suitable for planting in woodland gardens. Shelter from wind is required, to prevent damage to its leaves.
