Iris ensata, commonly called Japanese iris or Japanese water iris, is a beardless perennial iris that grows in slowly expanding clumps to 60-120cm tall.
Sword-shaped, linear green leaves (up to 60cm long) have prominent midribs. Huge flowers (typically 10-15cm across) have a distinctively flattened appearance. Cultivars come in single, double and peony flowered forms in a wide range of colours including shades of blue, lavender, violet-red, pink and white. Blooms early to mid summer (later than both Bearded and Siberian iris).