Iris are a large and diverse group of perennials that grow from either bulbs or rhizomes. The California native Douglas iris and cultivars known as Pacific Coast Hybrids are an excellent choice for summer-dry gardens and understory plantings. Fall rain brings new growth in the form of thin, upright leaves, followed in late winter to early spring by the first blossoms. Douglas iris commonly ranges in color from lavender to purple, but cultivars are available in a range of colors including white and yellow. Established plantings can be lifted and divided after the first significant fall rain and either replanted or put into containers to share with others.