Rhododendron rex

Rhododendron rex is an exceptional plant, a true star of the shade in spring. This vigorous Chinese species stands out for the size of its vegetation, the beauty of its foliage, and its bountiful delicately coloured spring flowering. If the conditions are met, in humus-rich and acidic soil, with some protective shade and under a mild and humid climate, it will form a true small tree that will be appreciated throughout the year. Its silvery young shoots are surrounded by very large velvety chamois leaves and serve as a setting for large inflorescences laden with white flowers slightly tinged with pink and delicately speckled with crimson-purple. Quite simply a wonder! 

Rhododendrons belong to the family of Ericaceae, just like heathers. They are divided into 'sections', grouping certain botanical characteristics and cultural requirements. Rhododendron rex, cultivated since 1913, is classified in the subgenus Hymenanthes, section Pontica, and subsection Falconera. 

Rhododendron rex exists in three forms, three subspecies distinguished by the size of the leaves as well as the colour and persistence of the indumentum, a kind of velvety coating present on the undersides of the leaves. It is a species native to China, specifically from pine forests located at high altitudes (between 2300 and 4000 m (7546 and 13123 ft)) in the southwest of Sichuan, southeast of Xizang, north and west of Yunnan, as well as northeast of Myanmar in Burma. 

This Rhododendron is quite bushy, taller than it is wide. In favourable climates, it reaches maturity about 2.50 m (8 ft) tall and 2 m (7 ft) wide (5 to 7 m (16 to 23 ft) tall in the wild). It is a rather slow-growing plant, but very vigorous and hardy up to -15°C (5°F) when mature. The branches, solidly structured, are covered with oversized evergreen foliage, oval-shaped, thick, and leathery. Some leaves can reach up to 50 cm (20 in) in length. On average, they will measure 20 to 30 cm (8 to 12 in) in length. They emerge covered with a silvery fuzz and surrounded by purplish leaf bracts. The mature leaves have a satin-like, smooth upper surface, green-blue in colour, and a velvety chamois underside tinged with rust. In April-May, its spectacular flowering begins with the appearance of large clusters of scaly buds tinged with bright pink. These inflorescences are corymbs that bear 15 to 25 large flowers. The pink buds open into almost white flowers, delicately shaded with pink, speckled with very dark purple, and marked with crimson in the throat. The flower's throat also hosts beautiful stamens with dark anthers. 

Rhododendron rex, a sumptuous shrub of ericaceous soil, will find its place in shade or partial shade in a moist, humus-rich, and well-drained soil with an acidic pH. While it is hardy, it will only reach its full potential in a humid and moist climate, far from the scorching sun. It can be used as a solitary plant, in a hedge, or in a large shrub bed, especially with other ericaceous plants. It can be paired with Chinese azaleas, with their pastel flowers complementing their warm tones perfectly, magnolias, andromedas (Pieris), mountain laurels (Kalmia), Japanese maples with yellow, green, or purple foliage... It can also be tried in a very large container on the terrace, still in partial shade and in a sheltered position from cold and dry winds, taking care to provide it with fertilizer and rainwater (or lime-free water) for watering.