Monkshood has been in cultivation for a very long time. Herbalists were writing about its toxic properties as early as the sixteenth century. It is a lovely addition to the back of the perennial border but all parts of the plant are extremely poisonous. Be sure to wash your hands after pruning plants.
Description of monkshood: Showy dark blue flower spikes open in late summer or early fall. Individual flowers are shaped like a helmet or a hood. The leaves resemble delphinium foliage. Plants grow 3 to 4 feet tall.
How to grow monkshood: Aconitum grows best where night temperatures regularly fall below 70 degrees Fahrenheit. Plant in full sun in cooler regions. Provide afternoon shade in warmer regions. Soil should be high in organic matter and moist but not swampy. Plant tubers early enough in the fall so that the roots have time to get established before the frost. Set the crowns just below the surface and do not disturb plants after they have been placed in the garden. Monkshood is long-lived and does not react well to division or transplanting.
Propagating monkshood: By seed (it must be fresh).
Uses for monkshood: Use in groups of three or five at the back of the garden. Monkshood makes an excellent cut flower but be careful not to get its sap on cuts or wounds.
Monkshood related varieties: 'Bressingham Spire' has compact stems with deep violet-blue flowers on 3-foot-tall stems that bloom from midsummer through fall. 'Carneum' has pale rose-pink flowers on 4- to 5-foot stems. Flower color is best in cool climates.
Scientific name for monkshood: Aconitum napellus