Monkshood is an upright, 2 to 4 foot high perennial with lovely blue-violet, spiked flowers that appear in mid-to-late summer. The distinctive, helmet-shaped flowers resembling the hood of a monks cape, thus the common name. All parts of this plant is poisonous, especially the bulbous roots, and should be planted with caution, especially near vegetable gardens and where children play.
All Common Names:
Tree or Plant Type:
- Mixed border,
- Large plant (more than 24 inches),
- Medium plant (12-24 inches)
- Partial sun/shade (4-6 hrs light daily)
- Zone 3,
- Zone 4,
- Zone 5 (Chicago),
- Zone 6,
- Zone 7
- Moist, well-drained soil
Season of Interest:
- Mid summer,
- Late summer,
- Early fall
Flower Color & Fragrance:
Shape or Form:
An upright, erect perennial reaching 2 to 4 feet high and 1 to 2 feet wide
All parts of plant is poisonous, especially the roots, so wear gloves and taken precaution when working with this plant.
Best in part shade in a moist, rich organic soil. If planted in sun, maintain soil moisture to avoid scorch. Water in dry periods.
Best left undisturbed, slow to recover from division. Plants prefer cooler growing conditions and will not tolerate hot summer temperatures.
Deadhead flowers to promote secondary growth. Cut back foliage in spring to promote bushier growth.
Staking may be necessary to control height.
Disease, pests, and problems
Mites, powdery mildew, verticillium wilt, and crown rot in wet soils.
Disease, pest, and problem resistance
Deer and rabbits
Native geographic location and habitat
Found in moist pastures and mountain areas in Central and Western Europe and Asia.
Alternate, dark green, 3 to 5 inch wide, palmately-shaped and divided at base.
Upright, terminal spikes, violet-blue with enlarged upper sepal, resembling the hood of a monk's cape.
Flowers appear in mid-to-late summer.
Flowers similar to Delphinium but Monkshood has 2 petals and Delphinium has 4.