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. The beautiful foliage is very resistant to deer browsing and it can form a very effective tall ground cover in deep shade.

Medicinal uses: Blue cohosh was used medicinally (powder rhizomes) by 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: the seeds are hydrophilic to extreme, they need to be sown soon after collecting or kept moist at all times for later sowing. The embryos are immature at the time the seeds mature.
Sow fresh seeds in the fall outdoors or sow moist packed seeds anytime, when weather allows. Cross-sections through seeds revealed fully developed embryos only by the second year. So, repeated cycles of warm/moist followed by cold/moist are needed for embryo growth and for breaking the dormancy.
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.