About
Rhododendron williamsianum, Williams' rhododendron, is a compact, spreading evergreen shrub to 1�1.5 m with neat, rounded to heart-shaped leaves that are bronze when young and glaucous beneath. Bell-shaped, soft rose-pink flowers 5 cm across are borne in small trusses in mid spring. One of the most popular and ornamental compact rhododendrons for a sheltered, moist, acid garden.
About the genus
Rhododendron, the rhododendrons and azaleas, are a vast genus of evergreen and deciduous shrubs and trees producing simple leaves � sometimes with a dense, colourful indumentum beneath � and funnel-shaped, bell-shaped or tubular flowers in a wide range of colours in spring and early summer. They thrive in moist, acid, humus-rich, well-drained soil in dappled shade.
Growing conditions
SunlightPartial shade
Soil typeClay, Loam, Sand
Soil pHAcid
Soil moistureMoist but well-drained
AspectNorth-facing, South-facing, West-facing, East-facing
ExposureSheltered
UK hardinessH5
Plant details
Plant typeShrubs
HabitBushy
FoliageEvergreen
Height1-1.5 metres
Spread1-1.5 metres
Time to full height10-20 years
Suggested usesCity and courtyard gardens, Cottage and informal garden
Native toSW China
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