About
Rhododendron rigidum is an evergreen shrub usually to about 2 m in cultivation with elliptic, brownish young leaves maturing to dark green with sparse yellow-brown scales beneath. In mid to late spring it produces loose clusters of widely funnel-shaped, almost flat, white, rose-pink or lilac flowers, sometimes with red flecks on the upper petals. A rewarding and graceful rhododendron for a sheltered, moist, acidic garden.
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
AspectNorth-facing, West-facing
ExposureSheltered
UK hardinessH5
Plant details
Plant typeHerbaceous Perennial
HabitColumnar upright, Spreading branched
FoliageEvergreen
Height1.5-2.5 metres
Spread1.5-2.5 metres
Time to full height5-10 years
Suggested usesCity and courtyard gardens, Cottage and informal garden
Native toChina (N Yunnan, SW Sichuan)
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, humus rich, acidic soil, in partial or dappled shade. Choose a site away from frost pockets and sheltered from strong winds, and do not allow plants to dry out. Mulch annually, ideally with leaf mould. See rhododendron cultivation for more detailed advice
PruningMinimal pruning required, see pruning group 8 (evergreens)
PropagationPropagate by semi-ripe cuttings in late summer, by layering in autumn, or by grafting in 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 powdery mildews, honey fungus, silver leaf and Phytophthora, as well as more specific Rhododendron diseases