Plate 1 figs. a–h · 8 separate observations
Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.
Native range 32 botanical countries
| Region | TDWG code | Continent |
|---|---|---|
| Connecticut | CNT | NORTHERN AMERICA |
| Delaware | DEL | |
| District of Columbia | WDC | |
| Illinois | ILL | |
| Indiana | INI | |
| Iowa | IOW | |
| Kentucky | KTY | |
| Maine | MAI | |
| Manitoba | MAN | |
| Maryland | MRY | |
| Massachusetts | MAS | |
| Michigan | MIC | |
| Minnesota | MIN | |
| Missouri | MSO | |
| Nebraska | NEB | |
| New Brunswick | NBR | |
| New Hampshire | NWH | |
| New York | NWY | |
| North Carolina | NCA | |
| Nova Scotia | NSC | |
| Ohio | OHI | |
| Ontario | ONT | |
| Pennsylvania | PEN | |
| Prince Edward I. | PEI | |
| Québec | QUE | |
| Rhode I. | RHO | |
| South Carolina | SCA | |
| Tennessee | TEN | |
| Vermont | VER | |
| Virginia | VRG | |
| West Virginia | WVA | |
| Wisconsin | WIS |
Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.
Flowering 171 in flower of 176 examined
Peak flowering in Aug. Each bar is the share of Oenothera perennis observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 171 of 176 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 9 months have fewer than 5 examined observations, so no proportion is drawn for them. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.cgje2x.
Also published as 17 synonyms
A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.
- Kneiffia gracilis (Fisch. & C.A.Mey.) Bartl.
- Kneiffia michauxii Spach
- Kneiffia perennis (L.) Pennell
- Kneiffia pumila Spach
- Oenothera chrysantha Michx.
- Oenothera gracilis Schrad. ex Fisch. & C.A.Mey.
- Oenothera perennis f. rectipilis (S.F.Blake) B.Boivin
- Oenothera perennis var. perennis
- Oenothera perennis var. rectipilis (S.F.Blake) S.F.Blake
- Oenothera perennis var. typica Munz
- Oenothera pumila L.
- Oenothera pumila var. chrysantha Gordinier & Howe
- Oenothera pumila var. minima Lehm. ex Hook.
- Oenothera pumila var. pusilla (Michx.) Torr. & A.Gray
- Oenothera pumila var. rectipilis S.F.Blake
- Oenothera pusilla Michx.
- Oenothera riparia Lehm.
Sourcesevery claim on this page
- World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
- iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
- Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
- Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.
We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.