Aristea major

Aristea major (Iridaceae) is an evergreen rhizomatous perennial native to South Africa, where it grows in damp conditions along streams and wetlands. It forms an upright clump of sword-shaped leaves up to 1.5 m tall, topped in summer by striking, star-shaped blue flowers that attract birds and butterflies. Grow in full sun, in moist to wet, well-drained soil; ideal at the edge of a pond, though its spreading rhizomes can become invasive.