Upright Yellow Woodsorrel (Oxalis stricta) is in the Woodsorrel Family family (Oxalidaceae). Across the U.S., iNaturalist users have logged 1,065 research-grade flowering observations of it in our sample, peaking in August.
Nationally it blooms mainly from June to September, but timing varies a lot by state and elevation — see the table below.
When to photograph Upright Yellow Woodsorrel: observations by month (U.S.)
About Upright Yellow Woodsorrel
Oxalis stricta, called the common yellow woodsorrel (or simply yellow woodsorrel), common yellow oxalis, upright yellow-sorrel, lemon clover, or more ambiguously and informally "sourgrass" or "pickle plant", is a herbaceous plant native to North America, parts of Eurasia, and has a rare introduction in Britain. It tends to grow in woodlands, meadows, and in disturbed areas as both a perennial and annual. Erect when young, this plant later becomes decumbent as it lies down, and branches...From Wikipedia via iNaturalist — article, CC BY-SA.
Upright Yellow Woodsorrel by state
| State | Observations | Peak month | Main season |
|---|---|---|---|
| New York | 521 | August | Jun–Sep |
| Vermont | 97 | August | Jun–Sep |
| Ohio | 54 | August | Jul–Oct |
| Massachusetts | 45 | July | May–Oct |
| North Carolina | 43 | August | Jun–Aug |
| Michigan | 42 | August | Jun–Sep |
| Pennsylvania | 38 | August | Jun–Sep |
| Illinois | 35 | May | May–Aug |
| Wisconsin | 24 | June | Jun–Sep |
| Virginia | 22 | April | Apr–Oct |
| Maine | 21 | August | Jun–Sep |
| Maryland | 18 | September | Jul–Sep |
| New Hampshire | 17 | August | Jun–Sep |
| Minnesota | 13 | August | Jun–Sep |
| Connecticut | 12 | August | Aug–Aug |
| Indiana | 11 | May | May–Sep |
| New Jersey | 11 | May | May–May |
| Kentucky | 6 | May | May–Aug |
| Rhode Island | 5 | September | Aug–Sep |
| Tennessee | 5 | August | Aug–Aug |
Main season = months with at least 30% of the state's peak-month count.
Related wildflowers (Woodsorrel Family)
Bermuda buttercup
Violet Woodsorrel
Redwood Sorrel
Mountain Woodsorrel
Largeflower pink-sorrel
Oregon woodsorrel
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 Upright Yellow Woodsorrel?
Nationally, August has the most observations, with the main season from June to September.
Where is Upright Yellow Woodsorrel most often seen?
The most observations come from New York, Vermont, Ohio.