Iris, Purple Flame Blue Flag IrisPurple Flame Blue Flag Iris is a marginal deciduous perennial with a clumping habit and long, lightly arched green sword like foliage that emerges bold purple. Long sturdy stalks grow from the center of the plant and are topped with soft bluish purple flowers with a central yellow splotch surrounded by a white zone from late spring into summer, attracting bees. Grows best in rich, slightly acidic, moist to wet water retentive soils. Iris versicolor is