Hairy Bittercress (Cardamine hirsuta) is in the mustard family family (Brassicaceae). Across the U.S., iNaturalist users have logged 2,649 research-grade flowering observations of it in our sample, peaking in March.
Nationally it blooms mainly from February to April, but timing varies a lot by state and elevation — see the table below.
When to photograph Hairy Bittercress: observations by month (U.S.)
About Hairy Bittercress
Cardamine hirsuta, commonly called hairy bittercress, is an annual or biennial member of the mustard family (Brassicaceae), and is edible as a bitter herb. It is a common weed in moist areas and has been transported to many new regions by humans.From Wikipedia via iNaturalist — article, CC BY-SA.
Hairy Bittercress by state
| State | Observations | Peak month | Main season |
|---|---|---|---|
| Pennsylvania | 294 | March | Mar–Apr |
| Oregon | 289 | March | Mar–Apr |
| New York | 274 | April | Mar–Apr |
| Massachusetts | 215 | April | Mar–Apr |
| Kentucky | 211 | March | Mar–Mar |
| New Jersey | 164 | March | Mar–Mar |
| Washington | 139 | March | Feb–Apr |
| Maryland | 138 | March | Mar–Mar |
| Virginia | 111 | March | Mar–Mar |
| Ohio | 109 | March | Mar–Apr |
| Delaware | 82 | March | Mar–Apr |
| Arkansas | 59 | February | Feb–Mar |
| California | 56 | February | Jan–Feb |
| Tennessee | 52 | March | Feb–Mar |
| Michigan | 47 | April | Apr–Apr |
| North Carolina | 47 | March | Feb–Mar |
| Georgia | 44 | February | Feb–Mar |
| West Virginia | 41 | March | Mar–Mar |
| Illinois | 34 | March | Mar–Apr |
| Indiana | 31 | March | Mar–Mar |
| Missouri | 31 | March | Feb–Mar |
| Alabama | 30 | February | Feb–Mar |
| Connecticut | 30 | April | Mar–Apr |
| Mississippi | 24 | February | Feb–Mar |
| District of Columbia | 20 | March | Feb–Mar |
| Oklahoma | 15 | March | Feb–Mar |
| Texas | 15 | February | Feb–Feb |
| Rhode Island | 12 | March | Mar–Apr |
| Idaho | 9 | April | Mar–Apr |
| South Carolina | 5 | February | Feb–Mar |
| Vermont | 5 | April | Apr–Apr |
Main season = months with at least 30% of the state's peak-month count.
Related wildflowers (mustard family)
Garlic Mustard
Dame's Rocket
Annual Honesty
Cut-Leaved Toothwort
Milkmaids
Shepherd's-Purse
Western Wallflower
Wild radish
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 Hairy Bittercress?
Nationally, March has the most observations, with the main season from February to April.
Where is Hairy Bittercress most often seen?
The most observations come from Pennsylvania, Oregon, New York.