Rhododendron simsii (EA)
Indian azalea
A tender evergreen or semi-evergreen azalea up to 2m high, with a branching habit and broadly ovate leaves. Produces funnel-shaped, carmine to rich red flowers, with darker red spots on the narrow petals, in pairs or small clusters at the tips of the stems in late spring. This species was a common parent for Indica hybrids
Size
Ultimate height
1.5–2.5 metresTime to ultimate height
5–10 yearsUltimate spread
1.5–2.5 metresGrowing conditions
Moisture
Moist but well–drainedpH
AcidColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Pink Red | Green | ||
|---|---|---|---|---|
| Summer | Green | |||
| Autumn | Green | |||
| Winter | Green |
Position
- Partial shade
Aspect
North–facing or West–facing
Exposure
Sheltered Hardiness
H4Botanical details
- Family
- Ericaceae
- Native to the UK
- No
- Foliage
- Evergreen or Semi evergreen
- Habit
- Spreading branched
- Potentially harmful
- Harmful 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
- Genus
Rhododendron can be evergreen or deciduous shrubs or trees, with simple leaves, sometimes with a dense colourful indumentum of hairs on the lower side, and funnel-shaped, bell-shaped or tubular flowers that may be solitary or in short racemes
- Name status
Correct
- Horticultural Group
- Evergreen azaleas are compact evergreen shrubs with small leaves and terminal racemes of small, funnel-shaped, usually unscented flowers in early summer
- Plant range
- Burma, Thailand, China
How to grow
Cultivation
May be grown outdoors in frost free areas, otherwise best grown under glass or in containers that can be moved indoors over winter. Grow in moist but well-drained, humus rich, acidic soil or in an ericaceous potting mix, and position in partial or dappled shade. See rhododendron cultivation for more detailed advice
Propagation
Propagate by semi-ripe cuttings in late summer, or by grafting in winter
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Patio and container plants
- Conservatory and greenhouse
- Flower borders and beds
- Wall side borders
Pruning
Generally requires minimal pruning, though may need restrictive pruning if grown under glass; see pruning group 8 (evergreens). Deadhead if practical, to promote vegetative growth rather than seed production
Pests
May be susceptible to vine weevil, rhododendron and azalea whitefly, rhododendron leafhopper, Pieris lacebug, scale insects, caterpillars and aphids
Diseases
May be susceptible to powdery mildews, honey fungus, silver leaf and Phytophthora, as well as more specific Rhododendron diseases
Get involved
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