About

Aconitum japonicum is a robust perennial that typically reaches a height of approximately 1 meter. It features deeply lobed, shiny dark green foliage, with leaves measuring up to 16 centimeters in length. In late summer, this plant produces panicles of hooded flowers in a rich blue hue.

About the genus

Aconitum consists of herbaceous perennials or biennials characterized by lobed foliage and clusters of hooded flowers arranged in racemes or panicles.

Growing conditions

Sunlight
Full sun, Partial shade
Soil type
Clay, Loam
Soil pH
Acid, Alkaline, Neutral
Soil moisture
Moist but well-drained
Aspect
West-facing, East-facing, North-facing
Exposure
Sheltered
UK hardiness
H7

Plant details

Plant type
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, Wildlife gardens
Native to
Japan
Toxicity
TOXIC if eaten, avoid skin contact. Wear gloves and other protective equipment when handling. Pets: TOXIC if eaten, avoid skin contact - see the HTA guide to potentially harmful plants for further information and useful contact numbers

Care notes

Cultivation
Best grown in moisture-retentive fertile soil in partial shade but sun and most soils are tolerated
Pruning
No pruning required except cutting back dead stems; use protective gloves
Propagation
Propagate by division in autumn or late winter to maintain vigour, although plants can be slow to re-establish. Use gloves when handling plants
Pest resistance
May be susceptible to aphids
Disease resistance
May be susceptible to fungal stem rot, powdery mildews, and Verticillium wilt