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. Propagated is by divisions of the root or by seeds.
The derivation of the genus name, Aconitum, is disputed but may come from a Greek word ἀκόνιτον (akoniton) which may come from the Greek word ἀκόν (akon) meaning dart or javelin, the tips of which were dipped in poison.
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 Southwest have resulted in at least 2 native species of monkshood there but they may be native to other regions also. The monkshood described here are native to at least one state in the Southwest.
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: Arizona and New Mexico as well as places in the Pacific Coast, Rocky Mountain area, Midwest and Mid-Atlantic
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
Arizona Monkshood (Aconitum infectum)
Erect to twining or reclining stems carry deeply lobed leaves and blue, occasionally white, hooded flowers. Little is recorded about this species.
Alternate Name/s: None
Native Range: Endemic to Arizona
Habitat: Wet areas such as spring-fed bogs, seep areas, meadows, and along streams in woodlands and grasslands at elevations of 2900-3350 m
Type: Perennial
Height: 8′
Bloom Time: Mid to late summer
Bloom Color: Blue, white
Light: Unavailable
Soil: Unavailable
USDA Hardiness Zones: 6-? (guestimate based on location of existing populations)
Photo Credit: USDA
For the purpose of this article, the Southwest includes the states of Texas, Oklahoma, New Mexico and Arizona. Other states often associated with the Southwest are included in other geographic areas. The key factor linking these four states is aridity. The area includes high dry plains and true deserts as well as spurs of the Rocky Mountains. Only Texas has a coast on the ocean which brings more precipitation and humidity to east Texas and Oklahoma than elsewhere in the area. In addition to the ocean, the Rio Grande and Colorado Rivers are significant water features in the area. Although temperatures in the mountains can be cool, most of the area experiences hot temperatures for a long period each year.