Articles
Rain Garden Plants: Blue Flag Iris
One-page informational sheet with details and pictures of blue flag iris (Iris versicolor).
Updated:
August 18, 2021
Blue flag’s swordlike leaves emerge from thick, horizontal rootstock (corm), which is covered with fibrous roots. Flowering stalks produce three to five showy flowers. Minor skin irritation can occur upon contact with seeds or cell sap. Attracts hummingbirds. Foliage is unpalatable to deer and other herbivores.
Height: 24 to 30 inches
Bloom color: Blue, purple
Bloom time: May to June
Hardiness zones: 4 to 9
Salt tolerance: Moderate
Spreading habit: Spreads by self-seeding and extension of rhizomes

Site Conditions
Sun: Sun/partial shade
Soil: Organic, acidic (pH < 6.8)
Hydrologic zones: Wet/moist, 0 to 6 inches, can tolerate complete submergence

Source
Lady Bird Johnson Wildflower Center
Prepared by Jessica Chou, Jodi Sulpizio, and Constance Schmotzer.











