Blue Cohosh (Caulophyllum thalictroides) is in the barberry family family (Berberidaceae). Across the U.S., iNaturalist users have logged 1,358 research-grade flowering observations of it in our sample, peaking in April.
Nationally it blooms mainly from April to May, but timing varies a lot by state and elevation — see the table below.
When to photograph Blue Cohosh: observations by month (U.S.)
About Blue Cohosh
Caulophyllum thalictroides, blue cohosh, a species of Caulophyllum (family Berberidaceae), also called squaw root or papoose root, is a flowering plant in the Berberidaceae (barberry) family. It is a medium-tall perennial with blue berry-like fruits and bluish-green foliage.From Wikipedia via iNaturalist — article, CC BY-SA.
Blue Cohosh by state
| State | Observations | Peak month | Main season |
|---|---|---|---|
| Tennessee | 167 | April | Apr–Apr |
| North Carolina | 152 | April | Apr–Apr |
| Illinois | 125 | April | Apr–Apr |
| Pennsylvania | 118 | April | Apr–May |
| Wisconsin | 104 | May | May–May |
| Ohio | 93 | April | Apr–Apr |
| Vermont | 71 | May | May–May |
| Virginia | 70 | April | Apr–May |
| Indiana | 69 | April | Apr–Apr |
| Michigan | 67 | May | Apr–May |
| Minnesota | 54 | May | May–May |
| New York | 42 | April | Apr–May |
| Georgia | 31 | April | Mar–Apr |
| Massachusetts | 31 | May | Apr–May |
| Maryland | 30 | April | Apr–Apr |
| West Virginia | 23 | April | Apr–Apr |
| Kentucky | 22 | April | Apr–Apr |
| Maine | 18 | May | May–May |
| New Hampshire | 16 | May | May–May |
| Connecticut | 14 | May | May–May |
| South Carolina | 11 | March | Mar–Apr |
| New Jersey | 9 | April | Apr–May |
| Alabama | 7 | March | Mar–Apr |
| Iowa | 7 | May | Apr–May |
Main season = months with at least 30% of the state's peak-month count.
Related wildflowers (barberry family)
Photography tips
- Photograph flowers on calm, overcast mornings to avoid wind blur and harsh shadows.
- Get low: a shallow depth of field (f/2.8–f/5.6) isolates a bloom against soft color.
- Stay on trails — trampling meadows kills plants and ruins next year's display.
- Try a kaleidoscope abstract of a single bloom with our online kaleidoscope tool.
FAQ
When is the best time to photograph Blue Cohosh?
Nationally, April has the most observations, with the main season from April to May.
Where is Blue Cohosh most often seen?
The most observations come from Tennessee, North Carolina, Illinois.