Astilbe vs Goat's beard
Goat's beard looks like a giant white astilbe, and they are relatives. It is a North American native, up to six feet, a back-of-the-border plant for part shade. Astilbe is smaller, comes in pinks and reds as well as white, and needs soil that never dries out.
| Astilbe Astilbe x arendsii |  Goat's beardAruncus dioicus | |
|---|---|---|
| Size | 24 in tall, 18 in wide | 5 ft tall, 4 ft wide |
| Plant | 18 in apart | 3½ ft apart |
| Zones | 4 to 8 | 3 to 7 |
| Light | Part shade to shade | Full sun to part shade |
| Soil | Evenly moist, rich fertility | Evenly moist, rich fertility |
| Flowers | Late June to mid July; pink, red, white | Early June to late June; cream |
| Leaves | Fine, herbaceous | Medium, herbaceous |
| Job in a bed | Drift | Specimen |
| Pets | No toxicity recorded | No toxicity recorded |
| Deer | No record | Resistant |
| Native | No | Yes |
| Spread | Low risk | Low risk |
Rows where they differ are marked. Flowering times are for zone 5.
Which to choose
- Choose astilbe for more shade, warmer gardens (to zone 8) and a smaller space (24 in against 5 ft).
- Choose goat's beard for colder gardens (to zone 3), a native garden, more height (5 ft against 24 in) and more wildlife.
Can they grow together?
Yes: they are recorded as partners. Beside astilbe, goat's beard is in flower together for two weeks, from late June; tall enough (5 ft) to stand behind it; happy in the same moist soil. They share part shade and zones 4 to 7.
Read more: all about astilbe, and all about goat's beard, each with a bed the planner designed around it.