Can Irises Grow in Shade? A Guide to Different Species and Growing Conditions

Irises are a genus of perennial flowering plants in the Iridaceae family, native to temperate regions of the Northern Hemisphere and parts of tropical Africa. Most species of irises, such as bearded, Siberian, Japanese, etc., prefer full sun with partial shade in the late afternoon. However, the crested iris (Iris cristata) is an exception and prefers partial shade. Native to the eastern United States, the crested iris produces 4- to 6-inch-long leaves from spindle-shaped woody rhizomes and needs about 6 hours of sunlight a day, but can tolerate as little as 3 hours.The ideal conditions for most irises are full sun, with partial shade in the late afternoon.

This will reduce the risk of illness. In the eastern United States, the iris borer attacks all types of irises. While this pest may not kill the plant, it causes striped or spotted leaves and can cause rhizomes to become soft. The borer is a pink caterpillar that hides in the leaves and then begins to move towards the root zone.

As caterpillars feed on rhizomes, plants are exposed to a number of diseases, such as bacterial soft rot and leaf spot.You can leave dry seed stalks in the garden for visual interest in winter or add them to dry flower arrangements. Siberian lilies in rain gardens need moisture to establish themselves, but after a year or two the plants become drought tolerant.If borers are a serious problem in your garden, you'll find that Siberian irises are considerably more forgiving than other types of irises. The flowers of the Louisiana iris can be as subtle as wildflowers or nearly as large and showy as the bearded iris. There are several species found in family gardens, such as Neomarica longifolia, with yellow and mahogany flowers; the white flowers with brown and blue spots of Neomarica gracilis; and Neomarica northiana and the Neomarica caerulea, which does not walk and has blue-purple flowers.The original German iris has been hybridized both by plant breeders and by nature, resulting in thousands of cultivars and a rainbow of colors, as corresponds to the origin of the name of the plant, the Greek goddess of the rainbow, the iris.

Most irises are planted or divided and transplanted in late summer, so that the rhizomes or bulbs have time to establish themselves in the garden before winter. While most irises tolerate some shade, especially in warmer climates, the stinky iris (Iris foetidissima) is the most shade-tolerant of all iris species.Matching the right iris to the growing conditions in your garden is all it takes to enjoy growing these beautiful, easy-care perennials. Although known as Dutch irises (Iris hollandica), these sun-loving lilies are hybrids developed by Dutch growers. Rocky gardens and dry areas Bearded irises need moisture in spring, but once they finish flowering, the plants remain dormant and the rhizomes should be kept as warm and dry as possible.