Yellow flag iris

(Iris pseudacorus)

  • 3 - 6' tall
  • Blooms May to July
  • Flowers 2 - 4" wide, 3 upward curved petals and 3 downward curved sepals with brown to purple streaks
  • Multiple flowers along stems
  • Leaves overlap and arise from base, up to 35" long and 1 1/4" wide, sword-shaped, dark green with thickened middle
  • Fruit 2" brown capsules
  • Rhizomes 1/2 - 1 1/2" wide forming dense patches 20' long
  • Reproduces by seed and rhizomes

Known Distribution

There are few occurrences of this species documented in Colorado. View the knownNorth American Distribution Map.
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