Purple Cress (Cardamine douglassii) is in the mustard family family (Brassicaceae). Across the U.S., iNaturalist users have logged 1,234 research-grade flowering observations of it in our sample, peaking in March.
Nationally it blooms mainly from March to April, but timing varies a lot by state and elevation — see the table below.
When to photograph Purple Cress: observations by month (U.S.)
About Purple Cress
Cardamine douglassii (known by the common names limestone bittercress and purple cress) is a perennial forb native to the eastern and central United States as well as the province of Ontario in Canada, that produces white to pink or purple flowers in early spring.From Wikipedia via iNaturalist — article, CC BY-SA.
Purple Cress by state
| State | Observations | Peak month | Main season |
|---|---|---|---|
| Ohio | 374 | March | Mar–Apr |
| Kentucky | 294 | March | Mar–Mar |
| Indiana | 171 | March | Mar–Apr |
| Michigan | 132 | April | Apr–Apr |
| Illinois | 107 | April | Apr–Apr |
| Tennessee | 43 | March | Mar–Mar |
| New York | 36 | April | Apr–Apr |
| Pennsylvania | 30 | April | Apr–Apr |
| Virginia | 13 | March | Mar–Mar |
| Wisconsin | 10 | May | May–May |
| Arkansas | 7 | March | Mar–Apr |
| Missouri | 5 | March | Mar–Mar |
| North Carolina | 5 | March | Mar–Mar |
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
Hairy Bittercress
Shepherd's-Purse
Western Wallflower
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 Purple Cress?
Nationally, March has the most observations, with the main season from March to April.
Where is Purple Cress most often seen?
The most observations come from Ohio, Kentucky, Indiana.