Caulophyllum thalictroides

Description

 Blue cohosh is an impressive plant, easy to recognize in early spring by the strikingly beautiful purple, almost back shoots. The foliage will change later to green and resemble the meadow rue (Thalictrum), hence the epithet ‘thalictroides’. C. giganteum has a similar foliage, only the flowers differ in colour and it flowers a bit earlier. They are very difficult to distinguish later.
The small purplish or yellowish green flowers would not qualify for a beauty contest but not the same goes for the unusually blue seeds adorning the stems in the fall. It is very resistant to deer browsing and it can form a very effective ground cover in deep shade.

Medicinal uses: Blue cohosh was used medicinally (powder rhizomes) by various Indigenous Peoples, mainly to promote childbirth (‘squawroot’) but also for: anxiety, rheumatism, stomach cramps and genito-urinary dysfunctions. It is still used in modern herbal medicine, under medical attention, as a natural labor-inducing stimulant.

Germination: seeds need to be kept moist at all times if not sown right away. Sow fresh seeds in the fall outdoors or allow a warm/moist followed by cold/moist stratification and sow in the spring. Cross-sections through seeds revealed fully developed embryos only by the second year.
In short: two seasons of stratification (2 years) are required for good germination. GA3 and other treatments have no effect.

The large seeds can also be sown directly in the ground ‘in situ’ or in a large pot placed in the ground; choose a part-shaded/shaded position; water regularly when necessary. See the germination page for more info.