About

Rhododendron micranthum is an evergreen shrub to about 2.5 m with a spreading habit, small, narrowly ovate, brown-scaled leaves and dense clusters of 20 or more tiny, white flowers with prominent stamens from late spring into summer. An unusual and distinctive 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

SunlightFull sun, Partial shade
Soil typeClay, Loam, Sand
Soil pHAcid
Soil moistureMoist but well-drained
AspectEast-facing, North-facing, South-facing, West-facing
ExposureExposed, Sheltered
UK hardinessH6

Plant details

Plant typeShrubs
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, Korea
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. Position in partial or dappled shade, or in full sun in cooler spots where the soil does not 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 seed, 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