Description
Northern Blue Flag Iris (Iris versicolor), also called Blue Flag Iris, Harlequin Blue Flag, Northern Iris, or Wild Iris, is a striking native perennial known for its deep blue to violet blooms and tall, sword-like foliage. Blooming from May through July, it brings bold color to wet landscapes and attracts butterflies and hummingbirds.
It typically grows 2–3 feet tall and thrives in full sun to partial shade. This moisture-loving species prefers wet to mesic soils and can tolerate shallow standing water, making it a strong choice for rain gardens, marsh edges, streambanks, and pond margins.
Northern Blue Flag spreads by rhizomes and seed to form dense colonies over time, helping stabilize wet soils. Once established, it requires little maintenance. While it was historically used for medicinal purposes, its roots are toxic to humans and livestock and should be handled with care. The flower’s three-petal form has also been associated with symbolism—representing wisdom, faith, and courage.
It’s similar to other native irises like Dwarf Crested Iris (Iris cristata), which prefers drier woodland settings and stays much shorter, as well as Copper Iris (Iris fulva) and Southern Blue Flag (Iris virginica), which thrive in wetter, southern habitats. Together, these species cover a range of conditions while offering similar bold, recognizable blooms.
