Also known as wolfbanes, leopard’s bane, devil’s helmet, or blue rocket, these herbaceous perennials are native to the mountainous parts of the Northern Hemisphere in North America, Europe, and Asia, where they grow in the moist, well-drained soils of mountain meadows. They are a member of the buttercup family, Ranunculaceae, that also includes delphinium, anemone, and hellebores. Plants usually grow at least 3′ tall but may be prostrate, reclining or climbing. The leaves are dark green, and usually deeply palmately lobed or divided, with toothed margins. The flowers are usually carried in erect terminal racemes or panicles up to 8″ long from mid-summer to early fall and are blue to purple, occasionally white or yellow. Each flower is up to 1″ long and consists of five sepals and two to ten petals. One of the sepals forms a helmet-like structure that hides the two upper, larger petals with nectaries in their spurs. The remaining petals are small, reduced to scales, or non-forming.
Monkshood is easy to grow in cool, organically rich, consistently moist, well-drained soil and do not tolerate wet soil. Although they may be grown in full sun in the northern part of their range they need afternoon shade elsewhere. Plants do best when their roots are cool and moist but the majority of the leaves are exposed to sun. They do not tolerate high heat and humidity. Monkshoods are generally healthy but are susceptible to damage by a variety of fungi if grown in humid and/or overly wet conditions.
All parts of the plant contain highly poisonous alkaloids, especially the roots. Plant away from vegetable gardens and children’s play areas.
Photo Credit: Wikipedia
The environmental conditions in the Mid-Atlantic have resulted in at least 4 native species of monkshood there but they may be native to other areas too. The monkshoods described here are native to at least 1 state in the Mid-Atlantic.
Western Monkshood (Aconitum columbianum)
Hollow stems that are sometimes weak and reclining bear palmate leaves 2-6″ wide, usually with 3-5 deep divisions sometimes with toothed or clefted margins. Widely spaced hooded flowers are carried in simple or branched racemes and are blue, purple, white or cream-colored. Flowers attract bumblebees, hawkmoths and hummingbirds, and are good in the vase.
Alternate Name/s: Columbian monkshood
Native Range: New York as well as places in the Pacific Coast, Rocky Mountain area, Southwest, and Midwest
Habitat: Moist forests, stream banks, bogs, wet thickets, seep areas, and subalpine meadows
Type: Perennial
Height: 1-6.5′
Bloom Time: Mid to late summer
Bloom Color: Blue, purple, white, cream
Light: Shade
Soil: Average, moderately moist, well-drained
USDA Hardiness Zones: 3-8
Photo Credit: Izabelskrats, Wikimedia Commons
Norther Blue Monkshood (Aconitum noveboracense)
Branched or simple, often prostrate stems carry palmately divided leaves with 5-7 deeply cleft or coarsely toothed, wedge-shaped lobes. The lobes are 1-3.5″ wide and sometimes have fine hairs. The hooded flowers are carried in terminal panicles or racemes and are1″ long and deep purple to lavender-blue (rarely white). This species is considered by some scholars to be a variety of western monkshood, A. columbianum.
Alternate Name/s: Northern wild monkshood, New York monkshood
Native Range: New York as well as places in the Midwest
Habitat: Shaded to partially shaded cliffs, algific talus slopes, or on cool, streamside sites.
Type: Perennial
Height: 1-4′
Bloom Time: Mid to late summer
Bloom Color: Blue
Light: Shade
Soil: Sandstone or limestone, cool, moist, well-drained
USDA Hardiness Zones: 5-? (guesstimate based on location)
Photo Credit: Wikipedia
Trailing White Monkshood (Aconitum relinatum)
Erect to climbing or reclining stems carry leaves up to 5″ wide and and long, and divided into 3, or less likely 5, wedge or oval-shaped lobes with coarsely toothed margins. Ten or more hooded flowers appear in terminal racemes or panicles, or from upper leaf axils. Each flower is about 1″ long, creamy white or pale yellowish-white.
Alternate Name/s: Trailing wolfsbane
Native Range: Pennsylvania as well as places in the Southeast
Habitat: In mountain forests, along streams, and in shaded ravines, coves or seeps, at mid to upper elevations
Type: Perennial
Height: 6-8′
Bloom Time: Summer
Bloom Color: White
Light: Part shade with some afternoon sun in southern part of range
Soil: Humusy, consistently moist, well-drained, slightly acidic
USDA Hardiness Zones: 3-7 ?
Photo Credit: William S. Justice, USDA
Wild Monkshood (Aconitum uncinatum)
The slender, flexible stems may be erect or vine-like and gain support by growing on other plants. The palmate leaves are up to 6″ wide and long, and have 3-5, sometimes up to 9, lobes. The hooded flowers appear in terminal clusters and are 1″ long, and usually deep purple or purplish-blue, occasionally white. They attract pollinators including a variety of butterflies, moths and bees.
Alternate Name/s: Southern blue monkshood
Native Range: Pennsylvania and Maryland as well as places in the Midwest, Southeast and New England
Habitat: Moist to wet soils in forests along streams and in clearings
Type: Perennial
Height: 3-6′
Bloom Time: Late summer to mid fall
Bloom Color: Purple
Light: Dappled shade
Soil: Cool, humusy, consistently moist, well-drained, slightly acidic
USDA Hardiness Zones: 4-9
Photo Credit: Wikipedia
The Mid-Atlantic region includes Delaware, Maryland, New Jersey, New York, Pennsylvania, and the District of Columbia. The region is characterized by cold winters and hot summers, high humidity in summer along some areas along the coast, and precipitation between 32 and 52″ per year.