“Iris versicolor, commonly known as the larger blue flag iris, is an herbaceous herb that reaches 2 to 2.5 feet tall. It prefers to grow in rich, moist soils and is happy in wet areas of pond margins, wet meadows, and marshy areas where it multiplies naturally forming clumps.  It can also be grown in containers in ponds in up to 4 inches of standing water.  The larger blue flag iris is native to Canada and the United States spanning south from Nova Scotia into the middle and northeastern United States to Virginia.  Blue flag iris thrives in full sun and tolerates partial shade where it forms a mass of blue lavender to white blooms. The blooms are formed of three upright inner standards and three distinctly marked sepals or falls.  The large 4-inch flowers bloom in late spring to early summer with several (3-5) on a naked stalk of up to 30 inches.  They are variably colored blue to lavender and purple with yellow splotches, white markings and striking veining on the falls.  The leaves are narrow and strap-like 1 inch wide and up to 24 inches long crossing at the base to be fan-like.  Though the fruit forms as a capsule, this plant propagates best by division of the rhizomes after blooms fade.

“It’s specific epithet, versicolor, is derived from this plant’s ability to produce many-colored blooms while the common name, “flag”, comes from an old English word (flagge) for reeds and refers to its natural preference to wetlands.” (North Carolina Extension)