About
Rhododendron rex, the king rhododendron, is a very large evergreen shrub or small tree with magnificent dark-green leaves 25�45 cm long, felted beneath with pale-brown indumentum. In mid to late spring it bears rounded trusses of 12�15 bell-shaped, pale-pink and white flowers with a deep-red throat and spots. A majestic large-leafed rhododendron for a sheltered, moist, acidic garden in a mild climate.
About the genus
Rhododendron, one of the largest and most diverse shrub genera, includes evergreen and deciduous species and hybrids ranging from dwarf alpines to large trees, all preferring moist, well-drained, acidic soil in sheltered positions with dappled shade or full sun.
Growing conditions
SunlightPartial shade
Soil typeClay, Loam, Sand
Soil pHAcid
Soil moistureMoist but well-drained
AspectSouth-facing, North-facing, West-facing, East-facing
ExposureSheltered
UK hardinessH5
Plant details
Plant typeShrubs, Trees
HabitBushy
FoliageEvergreen
Height8-12 metres
Spreadwider than 8 metres
Time to full height20-50 years
Suggested usesCottage and informal garden, Architectural
Native toW China, Myanmar
ToxicityHarmful if eaten. Wear gloves and other protective equipment when handling. Pets (dogs, cats, rabbits, tortoises) Harmful if eaten - for further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
Care notes
CultivationGrow in moist but well-drained, leafy, humus-rich acid soil in part shade with shelter; see rhododendron cultivation
PruningPruning group 8
PropagationPropagate by seed when ripe, or semi-ripe cuttings in late summer, layering in autumn or grafting in late summer or late winter
Pest resistanceMay be susceptible to vine weevil, rhododendron and azalea whitefly, rhododendron leafhopper, pieris lacebug, scale insects, caterpillars and aphids
Disease resistanceMay be susceptible to various Rhododendron diseases including powdery mildews, rhododendron petal blight, rhododendron bud blast, silver leaf and honey fungus