Iris ensata, commonly named Japanese Iris, is a perennial growing to 2 feet to 4 feet tall. It is native to Japan, northern China to eastern Russia. Iris ensata grows in marshes, ditches, and other wet places, even in shallow water. The flowers are consisting of 3 sepals and 3 petals. The species has reddish-purple flowers; flowering in June and July. The huge flat flowers of this beautiful Iris are among the biggest of all. The falls flap open 6 to 8 inches wide, floating like opaque clouds atop the slender, green stems. The flowers are hermaphrodite, they have both male and female organs. The plant is self-fertile. Iris ensata develops narrow, sword-shaped leaves rising 3 to 4 feet tall or more. The plant spreads by means of its modified stems, rhizomes, which are located below the soil surface. Hardiness zones 5-9, (-26øC/-15øF, -5øC/25øF) in Winter. The plant prefers light sandy and medium loamy soils. The plant prefers slightly acid soil and well-drained soil. It requires moist or wet soil. Plants are then best kept in drier conditions over Winter. It cannot grow in the shade.