Native to the eastern United States, this towering perennial makes a great addition to moist, shaded gardens. Black snakeroot has handsome, dark green, triply divided leaves. In midsummer to early fall, it sends up tall, wiry stems topped with spikes of tiny, airy white flowers. The flower show lasts for at least a month, and small green seedpods keep the spikes attractive into late fall. Black snakeroot's impressive height and late-season bloom make it a unique element in perennial gardens.
Common name: Black snakeroot (also known as bugbane or black cohosh)
Botanical name: Cimicifuga racemosa
Plant type: Herbaceous perennial
Zones: 3 to 8
Height: 4 to 7 feet tall (in bloom)
Family: Ranunculaceae, buttercup family
- Sun: Plant in partial shade.
- Soil: Prefers moist, fertile soil with plenty of organic matter.
- Moisture: Needs evenly moist soil for best growth.
- Mulch: Use a thin layer of compost or shredded leaves if desired.
- Pruning: Cut back old stems in fall or early spring.
- Fertilizer: One light application of balanced fertilizer per summer, if needed.
- Seeds can be sown outdoors in fall. Seedlings will emerge in spring. Plant clumps can be divided in spring.
Pests and diseases
- Black snakeroot can suffer leaf scorch (browning of leaf margins) if soil is too dry.
- Tarnished plant bugs or rust disease may occasionally damage foliage.
- The flowers tend to repel bugs, which is where the common name "bugbane" comes from.
- Black snakeroot blooms as early as midsummer in the South, but waits until late summer or early fall in northern zones.
- The long spikes of white flowers are perfect for lighting up a shady garden.
- Combine black snakeroot with other moisture-loving perennials such as cardinal flower (Lobelia cardinalis), pink turtleheads (Chelone lyonii), and Joe Pye weed (Eupatorium fistulosum ‘Gateway').
- Though there are no cultivars of this species, there are several exciting cultivars of some closely related species (see below).
All in the family
- The buttercup family is home to many wonderful perennials, including delphiniums, columbines (Aquilegia), helebores (Helleborus), anemones, and monkshood (Aconitum).
- A related species, Cimicifuga simplex, is noted for the cultivar ‘Brunette' that sports stunning, deep bronzy purple foliage and pinkish white flower spikes. The cultivar ‘Hillside Black Beauty' also has rich purplish foliage. (Note: These are sometimes listed under the species name C. ramosa).
- C. simplex ‘White Pearl' is a more compact plant. The spikes of white flowers are especially long (over 2 feet).
(Text by Nancy Rose, photo by Amy Sumner)