Common Evening Primrose
Oenothera biennis L. is the correct and accepted scientific name for the Evening Primrose. Both the genus and species were named and described as such by Carl von Linnaeus in the first volume of the first edition of Species Plantarum in 1753.
As of 5-18-21, Plants of the World Online lists 119 synonyms for Oenothera biennis. You can view the list HERE (I didn’t want to list them all).
Plants of the World Online by Kew lists 154 species in the Oenothera genus (as of 5-8-21 when I last updated this page). It is a member of the plant family Onagraceae with 21 genera. Those numbers could change as updates are made by POWO.
The distribution map above for Oenothera biennis is from the USDA Plants Database. Areas in green are where the species is native in the United States and Canada.
Obviously, the distribution map above for Oenothera biennis from Plants of the World Online is quite a lot different for North America. I mainly wanted to include this map to show where the species had been introduced (areas in purple). I am sure someday soon this map will be updated… Normally, POWO is on the ball.
The map on iNaturalist shows where members have made observations. Anyone can join and it is a great website to confirm and share your observations.
THERE ARE SEVERAL LINKS AT THE BOTTOM OF THE PAGE FOR FURTHER READING AND TO HELP WITH A BETTER POSITIVE ID.
When I moved back to the family farm in west-central Missouri in 2013, I noticed this plant coming up in the cracks in the floor of what used to be the back porch of my grandparent’s old house. My dad said it always comes up there every year. I let it grow so I could figure out what it was. Well, it grew and powered but normally they were always closed by the time I got up and went outside. I was able to identify it as Oenothera biennis, the Evening Primrose, from photos on the Missouri Plants website.
Since 2013, I have been photographing and identifying wildflowers on the farm and other areas locally. The only place I have found the Oenothera biennis are in the cracks of the floor and now the flower bed behind the porch (which I built way back in the early 1980’s). I am the third generation on this farm and I first moved here after my grandfather passed away in 1981 (when I was 20). I think perhaps dad kept the plants in the cracks cut off because after I didn’t they started coming up “IN MASS” in the flower bed…
I apologize for not writing descriptions at the moment, but I have A LOT of wildflower pages to make and publish before I start getting too busy. I update this site and add new pages over the winter but I didn’t get finished. SO, I decided to just make the page with photos and links to other sites for better plant ID. I will be taking more photos over the summer and posting but I will also be working on these pages as I have time.
I have enjoyed photographing and learning about the many wildflowers growing on the farm and other areas. My farm is in Windsor, Missouri in Pettis County (Henry County is across the street and Benton and Johnson aren’t far away). I have grown over 500 different plants and identified over 100 species of wildflowers (most have pages listed on the right side of the page). I am not an expert, botanist, or horticulturalist. I just like growing, photographing, and writing about my experience. I rely on several websites for ID and a few horticulturalists I contact if I cannot figure them out. Wildflowers can be somewhat variable from location to location, so sometimes it gets a bit confusing. If you see I have made an error, please let me know so I can correct what I have written.
I hope you found this page useful and be sure to check the links below for more information. They were written by experts and provide much more information. Some sites may not be up-to-date but they are always a work in progress. If you can, I would appreciate it if you would click on the “Like” below and leave a comment. It helps us bloggers stay motivated. You can also send an email to me at firstname.lastname@example.org. I would enjoy hearing from you especially if you notice something is a bit whacky.
FOR FURTHER READING:
PLANTS OF THE WORLD ONLINE (GENUS/SPECIES)
INTERNATIONAL PLANT NAMES INDEX (GENUS/SPECIES)
WORLD FLORA ONLINE (GENUS/SPECIES)
USDA PLANTS DATABASE
USDA PLANT GUIDE
MISSOURI BOTANICAL GARDEN
MSU-MIDWEST WEEDS AND WILDFLOWERS
MISSOURI DEPARTMENT OF CONSERVATION
FRIENDS OF THE WILDFLOWER GARDEN
KANSAS WILDFLOWERS AND GRASSES
NORTH CAROLINA STATE UNIVERSITY
PFAF(PLANTS FOR A FUTURE)
LADY BIRD JOHNSON WILDFLOWER CENTER
MARYLAND BIODIVERSITY PROJECT
OHIO PERENNIAL AND BIENNIAL WEED GUIDE
UNIVERSITY OF WASHINGTON-BURKE HERBARIUM
NOTE: The data (figures, maps, accepted names, etc.) may not match on these websites. It depends on when and how they make updates and when their sources make updates (and if they update their sources or even read what they say). Some websites have hundreds and even many thousands of species to keep up with. Accepted scientific names change periodically and it can be hard to keep with as well. Some of the links may use a name that is a synonym on other sites. In my opinion, Plants of the World Online by Kew is the most reliable and up-to-date plant database and they make updates on a regular basis. I make updates “at least” once a year and when I write new pages or add new photos but I do get behind. We are all a work in progress. 🙂