- Blue Cohosh-Caulophyllum thalictroides Hardy Planting Zones- 4-7 Sun or Shade – Partial Shade to Full Sun Mature Height - 2-4' Mature Width- 1-2' Bloom Season – Spring (April-June) Gardener Status- Novice
Blue Cohosh - Caulophyllum thalictroides
Blue cohosh is native to states in the eastern half of the United States as well as some areas in Asia. The plant has a sturdy, upright stem and intricate blue-green foliage that grows from the middle of the stem. The three-lobed, veined leaves begin as a smoky blue color in spring and change to bluish-green later in the season, which compliments the beautiful clusters of blue seeds. These seed clusters can be used as lovely additions to autumn flower arrangements. Between April and June, half-inch yellow-green and brown-green flowers appear. These petite blooms each have six points. Native Americans relied on blue cohosh for widespread medicinal uses, especially for female issues. This plant enjoys shady woodland locations with moist, fertile soils. It prefers neutral to slightly acidic conditions as well as loamy, clay soil. Blue cohosh grown from seed will take about three or four years to flower and spreads slowly over time by rhizomes to reproduce colonies. Young versions have a white, waxy bloom. The blue cohosh plant is resistant to both insects and diseases. Blue cohosh can be planted by the roots around 2.5 centimeters thick and spaced about 30 to 40 centimeters apart. This perennial attracts birds, who are happy to help distribute the many seeds, and other wildlife to a backyard landscape. While providing both pollen and nectar to bees and other beneficial insects, the blue cohosh stands out nicely among other wildflowers, ferns, and sedges in a shade garden.