Ninebark 'Diabolo' vs Smokebush 'Royal Purple'
Both are grown for dark purple leaves. Ninebark is a North American native: tough, cold-hardy, with flat clusters of white flowers in early summer and peeling bark. Smokebush is from Europe and Asia, with rounder leaves and, in summer, the hazy flower plumes that give it its name; it colours brilliantly in autumn.
 Ninebark 'Diabolo'Physocarpus opulifolius 'Diabolo' |  Smokebush 'Royal Purple'Cotinus coggygria 'Royal Purple' | |
|---|---|---|
| Size | 8 ft tall, 8 ft wide | 11½ ft tall, 11½ ft wide |
| Plant | 6½ ft apart | 8 ft apart |
| Zones | 3 to 7 | 5 to 8 |
| Light | Full sun | Full sun |
| Soil | Well-drained, average fertility | Well-drained, average fertility |
| Flowers | Late May to late June; white | Early June to late July; pink |
| Leaves | Medium, deciduous | Medium, deciduous |
| Job in a bed | Anchor | Anchor |
| Pets | No toxicity recorded | Toxic to people |
| Deer | Not listed as resistant | Resistant |
| Native | Variety of a native | No |
| Spread | Low risk | Low risk |
Rows where they differ are marked. Flowering times are for zone 5.
Which to choose
- Choose ninebark 'Diabolo' for colder gardens (to zone 3), a native garden and more wildlife.
- Choose smokebush 'Royal Purple' for warmer gardens (to zone 8), deer country, a longer show (8 weeks of flower against 4) and more height (11½ ft against 8 ft).
Can they grow together?
Yes: they grow in the same conditions. Beside ninebark 'Diabolo', smokebush 'Royal Purple' is in flower together for three weeks, from early June. They share full sun and zones 5 to 7.
Read more: all about ninebark 'Diabolo', and all about smokebush 'Royal Purple', each with a bed the planner designed around it.