Shrub
Rose of Sharon
Hibiscus syriacus
A deciduous shrub with large, funnel-shaped flowers from summer into autumn. It starts spring growth late. Flowering is best in a warm, sunny, sheltered spot; mature size and flower appearance depend on the cultivar.
- Size
- 2.5–4 m high · 2.5–4 m wideVaries by cultivar
- Light
- Full sun / Partial shade
- Water
- Moderate
- Winter
- Hardy
- Seasonal form
- Deciduous
- Maintenance
- Moderate
Before planting
- Choose a warm, sheltered site and well-drained soil that retains moderate moisture. Sun favours flowering, though light partial shade is tolerated.
- Allow for a shrub about 2.5–4 m tall and wide, or check the mature dimensions of a smaller cultivar.
Why choose it
- Large flowers extend the border's display from summer towards autumn.
- It can grow as a loose shrub or be trained into a more orderly form.
Care
- Water during establishment and prolonged drought, but avoid keeping roots constantly wet.
- Hard pruning every year is unnecessary. If shortening is needed, do it in spring before new shoots develop; flowers form on current-season growth.
- Remove unwanted seedlings. Check local warnings about spread before planting; seed production differs between cultivars.
Good to know
- Late leaf emergence does not necessarily mean frost damage. Wait until its usual growth period before judging whether the shrub is alive.
- This is neither the tropical indoor hibiscus nor the species grown for calyx tea. Hardiness also depends on the site and climate.