Irises are members of the Iridaceae family of flowers. The unique shape of this distinctive flower's petals makes it easy to recognize even among the Conservatory Garden's many stately blooms. Blooming throughout March, April, and May, the Conservatory Garden's irises appear in deep, rich indigoes, blues, and violets. It is also possible to find irises in yellow, white, and multicolored varieties. Irises are perennial flowers, making them relatively simple to maintain from year to year. They are popular choices for ground cover, and tend to grow well alongside other types of plants.