About
Astilbe 'Amethyst' (x _arendsii_) is a perennial that forms clumps and reaches a height of up to 90 cm. It features dense, dark green foliage that is finely divided, complemented by dark red stems. In mid-summer, it produces elongated, airy plumes of dark purplish-pink flowers.
About the genus
Astilbe are perennial plants with rhizomes, characterized by their dissected leaves that typically have a ternate structure. In summer, they produce upright panicles filled with small flowers in shades of white, pink, or purple. The dried flower heads persist into autumn, adding interest to the landscape.
Growing conditions
- Sunlight
- Partial shade
- Soil type
- Clay, Loam
- Soil pH
- Acid, Alkaline, Neutral
- Soil moisture
- Moist but well-drained, Poorly-drained
- Aspect
- West-facing, East-facing, North-facing
- Exposure
- Sheltered
- UK hardiness
- H7
Plant details
- Plant type
- Bogs, Herbaceous Perennial
- Habit
- Clump forming
- Foliage
- Deciduous
- Height
- 0.5-1 metres
- Spread
- 0.1-0.5 metres
- Time to full height
- 2-5 years
- Suggested uses
- Cottage and informal garden
Care notes
- Cultivation
- Grow in moist but well-drained or boggy soil in dappled shade, or in indirect sun where the soil remains moisture-retentive in summer. Drought intolerant, may be damaged in hot sun. Good for waterside planting. See Astilbe cultivation
- Pruning
- Can cut back after flowering, or delay until spring as faded flower spikes can remain attractive in autumn and winter
- Propagation
- Propagate by division in late winter or early spring, pot divisions under glass and plant out in late spring
- Pest resistance
- May be susceptible to vine weevil damage
- Disease resistance
- May be susceptible to Powdery mildews and leaf scorch in hot sun