
Iris pseudacorus on 4-15-12, #86-47.
Yellow Flag, etc.
Iris pseudacorus
EYE-ris soo-DA-ko-rus
Iris pseudacorus L. is the correct and accepted scientific name of this species of iris. It was first described by Carl von Linnaeus in Species Plantarum in 1753. There are 33 synonyms of this species!
Plants of the World Online currently lists 299 accepted species in the genus Iris. This could change as they are still uploading data and there are always updates being made.
There was a good sized bed of these AWESOME Iris along the driveway at the mansion in Mississippi. Several years ago when I was doing plant research for the blog, I could have sworn that I found this species on the Louisiana Iris Society website and that it was a species of Louisiana Iris. In fact, the above photo was named Iris louisiana and my only source of information was online. Apparently, I was mistaken, because Iris pseudacorus IS NOT a species of Louisiana Iris.
There are six species considered to be Louisiana Iris, including Iris fulva, Iris hexagona, Iris brevicaulis, Iris giganticaerulea, Iris nelsonii and Iris savannarum. All natives of the southern USA. Iris pseudacorus is native to parts of Europe, western Asia, western Siberia, Turkey, Iran and northern Africa.

Iris pseudacorus on 6-14-09, #19-07.
One year they grew too over 6 feet tall. I took a photo, which I can’t seem to find, of a friend standing in front of them. He is 6’3 and the iris were taller than him. My first summer at the mansion, 2009, they flowered pretty well but after that, no. I decided that maybe the bed needed to be redone so I removed all the rhizomes, spaced them out better and planted them to the proper depth. There had been several bare spots, too. They didn’t seem mind but they did NOT flower the next year… Then I moved back to the family farm in mid-Missouri in February 2013.
USEFUL INFORMATION:
Family: Iridaceae
ORIGIN: Europe to western Siberia, Caucasus, Turkey, Iran, northern Africa
ZONES: USDA 5-9
HEIGHT: 3-5’ plus
BLOOM TIME: May-June
LIGHT: Full sun to part shade
WATER: Medium to wet. Plants can stand in water up to 12” deep.
PROPAGATION: Plants easily spread by rhizomes and self-seeding.
According to information I found online, these plants love water and can grow in water up to a foot deep! Even though they don’t like to dry out, I am positive proof that they are also very drought tolerant. They went through many years of no additional water at the mansion except what was provided by mother nature.
The rhizomes of Iris pseudacorus have been used as an herbal remedy and in water treatment for its ability to take up heavy metals.
GOOD SOURCES OF INFORMATION:
Go Botany is a website about plants in New England, and the Iris Pseudacorus is on this website.
I should have brought some of these with me when I moved back to the family farm in mid-Missouri in February 2013, but I didn’t… I know there are more photos somewhere, so someday I will search my Mississippi photos and see if I can find them.
I hope you enjoyed this page and maybe found it useful. If you have any comments, questions or suggestions, I would like to hear from you. Please click on “like” if you visited this page. It helps us bloggers stay motivated. 🙂 You can check out the links below for further reading. The links take you directly to the genus and species of this plant. If you notice I made an error, please let me know.