Rocky Mountain Iris will grow to be about 16 inches tall at maturity, with a spread of 3 feet. When grown in masses or used as a bedding plant, individual plants should be spaced approximately 30 inches apart. It grows at a medium rate, and under ideal conditions can be expected to live for approximately 10 years. As an herbaceous perennial, this plant will usually die back to the crown each winter, and will regrow from the base each spring. Be careful not to disturb the crown in late winter when it may not be readily seen!
This plant does best in full sun to partial shade. It is quite adaptable, prefering to grow in average to wet conditions, and will even tolerate some standing water. This plant does not require much in the way of fertilizing once established. It is not particular as to soil pH, but grows best in clay soils. It is highly tolerant of urban pollution and will even thrive in inner city environments. This species is native to parts of North America. It can be propagated by division.