Iris japonica is a native of China growing in open forest edges and grasslands, at elevations from 500 to 800 m (1,600 to 2,600 ft). One population at 2,400 to 3,400 m (7,900 to 11,200 ft) in Southwest China is believed to be naturalized, rather than native. The species is widely planted.
The pale blue flowers are 4.5 to 5.5 cm (1.8 to 2.2 in) wide, blooming in early spring
USDA Hardiness Zone 7-9