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Blue Flag Iris

Iris versicolor

Botanical illustration of Blue Flag Iris (Iris versicolor)

Botanical plate of Iris versicolor — Curtis-style illustration.

Plate 173 from American Medicinal Plants, Iris versicolor

Northern Blue Flag (Iris versicolor), Ottawa, Ontario

Iris versicolor or Iris versicolour is also commonly known as the blue flag, harlequin blueflag, larger blue flag, northern blue flag, and poison flag, plus other variations of these names, and in Great Britain and Ireland as purple iris. It is a species of Iris native to North America, in Eastern Canada and the Eastern United States. It is common in sedge meadows, marshes, and along streambanks and shores.

Quick Facts

Scientific name Iris versicolor
Family Iridaceae
Height 2-3 ft
Bloom time Jun-Jul
Sun Full sun to part shade
Moisture Wet
Soil Muck, loam
Wildlife value Shoreline stabilizer; worked by bumble bees and hummingbirds

Mentioned In

Image Credits

  • Charles Frederick Millspaugh (Public domain)
  • D. Gordon E. Robertson (CC BY-SA 3.0)

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