Aconitum chasmanthum
open-flowered monk's hood
Upright, clump-forming, herbaceous perennial, producing panicles of bright purple-blue, hooded flowers. These appear in late summer and autumn on stems up to 1.5m high, above dark green, leathery, palmate to deeply-divided, lobed foliage
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Size
Ultimate height
1–1.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Green | |||
| Autumn | Blue Purple | Green | ||
| Winter |
Position
- Full sun
- Partial shade
Aspect
East–facing or South–facing or West–facing
Exposure
Sheltered Hardiness
H7Botanical details
- Family
- Ranunculaceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Potentially harmful
- TOXIC if eaten, avoid skin contact. Wear gloves and other protective equipment when handling
- Genus
Aconitum can be herbaceous perennials or biennials with lobed leaves and racemes or panicles of showy, hooded flowers
- Name status
Correct
How to grow
Cultivation
Best grown in moisture-retentive fertile soil in partial shade but sun and most soils are tolerated. Staking may be necessary. See staking perennials for further advice
Propagation
Propagate by division every third year in autumn or late winter to maintain vigour, although plants can be slow to re-establish
Suggested planting locations and garden types
- Cottage and informal garden
- Wildlife gardens
- Flower borders and beds
Pruning
Tall stems can be pruned down later in autumn when flowering is finished
Pests
May be susceptible to aphids
Diseases
May be susceptible to fungal stem rot and Verticillium wilt
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