Data specific to Irises (Edit)
Classification: Species
Registered Height: 30-64 inches
Bloom Color Classification: Yellow

General Plant Information (Edit)
Life cycle: Perennial
Sun Requirements: Full Sun
Water Preferences: In Water
Wet
Wet Mesic
Flowers: Showy
Flower Time: Spring
Underground structures: Rhizome
Uses: Water gardens
Will Naturalize
Propagation: Seeds: Self fertile
Propagation: Other methods: Division
Other: Can be invasive
Pollinators: Hoverflies
Bees

Image
Common names
  • Yellow Flag
  • Species Iris
  • Iris
  • Fleur-de-Lis
Botanical names
  • Accepted: Iris pseudacorus
  • Synonym: Iris pseudacorus var. bastardii

Photo Gallery
Location: Western North Carolina
Date: 2015-05-03
  • Uploaded by vic
Location: My garden in Warrenville, SC
Date: 2018-04-27

Date: May
Image by Spencer C. H. Barrett, University of Toronto
Location: Maine
Location: Bea’s garden
Date: 2023-05-14

photo credit: H. Zell
Location: Nature Reserve Gent, Belgium
Date: 2009-05-07
Location: my Zone 7b garden in North Georgia Mountains
Date: 2023-04-21
Location: Savannah, Georgia (my garden)
Date: 2021-04-16
These came from our local plant swap and are 3 feet tall. Bloomin
Location: Bea’s garden
Date: 2023-04-03
Location: Oxfordshire, England
Date: 2016-06-09
Location: Botanical Gardens of the State of Georgia...Athens, Ga
Date: 2022-05-10
Yellow Flag Iris With A Green Lynx Spider 003
Location: Murray, Utah, United States
Date: 2018-04-11
Location: Coastal San Diego County 
Date: 2018-04-24
San Diego Zoo
Location: Fairfax, VA | July, 2022
Date: 2022-07-02
Location: Chapin, SC
Date: 2018-04-27
Located in our bog garden.

Date: 2007-05-07
Photo courtesy of: Photo2222
Location: Woodbridge , Va
Date: 2018-05-15
Location: Fairfax, Virginia (May 2022)
Date: 2022-05-21

Infestation photograph by Leslie J. Mehrhoff, University of Conne
Location: My garden

Date: c. 1937
illustration from the 1937 catalog, Robert Wayman, Bayside, New Y
Location: Oxfordshire, England
Date: 2016-06-14
happy in water or on land, tends to self-seed

Photo courtesy of Iris City Gardens
Location: Nature Reserve Gent, Belgium
Date: 2008-05-17
Location: Southern Pines, NC (Boyd House garden)
Date: May 13, 2023
Yellow Flag Iris # 219 nn; RAB p. 1183,53-5; AG p. 513, 113-1; LH

Date: c. 1869
illustration from 'English Botany', vol. 9, 1869
Location: Southern Pines, NC (Boyd House garden)
Date: May 13, 2023
Yellow Flag Iris # 219 nn; RAB p. 1183,53-5; AG p. 513, 113-1; LH

Photo courtesy of: Krzysztof Ziarnek, Kenraiz
Location: Orangeburg, SC
Date: 2014-04-23
Yellow flag Iris
Location: My garden
Location: my garden 
Date: 2013-03-23
Location: Karlsruhe, Germany. The plant is used in homeopathy as remedy: Iris pseudacorus (Iris-ps.)
Date: 2010-05-30
Photo courtesy of: H. Zell
Location: Tillage, Austin, Texas
Date: 2022-04-06
Location: Ontario, Canada
Date: 2012-06-09
Location: Ed Burton, NE Wisconsin
Date: 2015-06-05
Location: Gradignan, Gironde, France
Photo courtesy of Jean-Jacques MILAN, Wikimedia Commons
Location: Middle TN
Location: Middle TN

Date: c. 1927
illustration by Mary E. Eaton from 'Addisonia', 1927
Uploaded by treehugger

Photo Courtesy of Shikoku Garden Inc.
  • Uploaded by Joy
Location: Murray, Utah, United States
Date: 2018-03-28

Date: 2012-06-05
Location: my garden in Dawsonville, GA (zone 7b north Geogia mountains)
Date: 2021-04-29
Location: My garden

Courtesy Gardens in the Wood of Grassy Creek
  • Uploaded by vic

Credit florum
Location: z5a, Smith College Botanical Garden
Date: 2012-05-27
Informed they go to great lengths to prevent naturalization.
Location: Nature Reserve Gent, Belgium
Date: 2008-05-17

Photo Courtesy of Lazy S'S Farm Nursery.
  • Uploaded by Joy

Photo Courtesy of Lazy S'S Farm Nursery.
  • Uploaded by Joy
Location: Fairfax, VA | June, 2022
Date: 2022-06-03
Location: my garden 
Date: 2014-04-04
bud & open bloom
Location: Iris pseudacorus near pond in Kytin village in Prague-West District, CZ
Date: 2011-06-14
Photo courtesy of: Huhulenik
Location: Indiana zone 5
Date: 2015-06-26
Location: Indiana zone 5
Date: 2015-06-26

Date: 2008-10-23
Photo courtesy of: Qwert1234
Location: Allentown, Pennsylvania
Date: 2015-05-24

Photo courtesy of: G.-U. Tolkiehn
Location: Ebro Delta, Spain
Date: 2013-05-27
Photo courtesy of: Donald Hobern

Date: 2010-05-30
Photo courtesy of: H. Zell

Date: May
credit: John Cameron
Location: Karlsruhe, Germany. The plant is used in homeopathy as remedy: Iris pseudacorus (Iris-ps.)
Date: 2010-05-30
Photo courtesy of: H. Zell
Location: my garden in Dawsonville, GA (zone 7b north Geogia mountains)
Date: 2021-04-29
Location: Vancouver, BC, Canada
Date: 2023-05-28
Iris pseudacorus

Credit florum

Credit florum

Credit florum
Location: Iris pseudacorus near pond named Bzdinka near Dobris in Pribram District ,CZ
Date: 2011-06-08
Photo courtesy of: Huhulenik
Location: Kunming Botanical Garden, Kunming, Yunnan, China.
Comments:
  • Posted by eclayne (Pioneer Valley south, MA, USA - Zone 6a) on Feb 3, 2012 3:03 PM concerning plant:
    The Yellow Flag Iris is a native of Europe, northwestern Asia and northern Africa. A wetland Iris, pseudacorus propagates aggressively by both rhizomes and prolific self seeding.

    Per the USDA Plants Database, Noxious Weed Information:
    Connecticut: Invasive, banned
    Massachusetts: Prohibited
    Montana: Category 3 noxious weed
    New Hampshire: Prohibited invasive Species
    Oregon: "B" designated weed, Quarantine
    Washington: Class C noxious weed

    Additional invasive resources listing I. pseudacorus include “The Invasive Plant Atlas of the United States” http://www.invasiveplantatlas.... and “Invasive Plants of the U.S.” http://www.invasive.org/weedcd...

    Numerous sterile cultivars and hybrids of I. pseudacorus, notably the Pseudatas (I. pseudacorus x I. ensata), are available today for growing outside its native range.
  • Posted by Bonehead (Planet Earth - Zone 8b) on Feb 18, 2018 5:50 PM concerning plant:
    This is a Class C noxious invasive in the Pacific Northwest. Control is recommended but not required. It may sicken livestock although it is generally avoided by herbivores. It clogs small streams and irrigation systems, displaces native vegetation along streambanks, and reduces habitat for waterfowl and fish. It spreads quickly into large clumps in shallow water. It can be pulled by hand or machine, although some folks react to the resins in the leaves and rhizomes. It is extremely difficult to get all the roots and I have had poor luck trying to clear this thug from my pond (we've dug them up using a backhoe). I have also read that one can persistently cut all leaves and stems below the waterline, but have not tried that method. On the plus side, it is a pretty plant with showy yellow flowers. It is native to Europe, the Mediterranean, North Africa, and Asia Minor.
Plant Events from our members
piksihk On April 5, 2021 Bloomed
East border bed, the stalk was very short, hardly any
piksihk On March 2, 2019 Bloomed
piksihk On May 19, 2018 Obtained plant
Clump ftom GMB swap
piksihk On April 5, 2016 Transplanted
HW back fence under azalea
gardengus On May 18, 2016 Bloomed
AndreA33 On June 19, 2015 Obtained plant
From BG
WebTucker On May 13, 2023 Bloomed
» Post your own event for this plant

Discussion Threads about this plant
Thread Title Last Reply Replies
Very invasive in some areas. by PollyK Oct 3, 2011 9:16 PM 0
Not Acorus calamus by pardalinum May 3, 2015 2:29 PM 2

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