This tough little plant grows well in shade or full sun, if planted in rich, well-drained organic soil that doesn’t stay too wet or too dry. When planting, don’t cover the tops of the small rhizomes with soil or they will rot. Water well during dry spells. In a border, crested iris will soon outgrow its position, so divide it after a few years and place the surplus plants in the woods where they can wander at will. It is prey to slugs, which devour the delicate blooms like candy. (See page 114 for how to get rid of this pest.)
The crested iris is a choice dwarf that adapts well to cultivation. It has sparkling, sweetly scented 2-inch blossoms that vary from pale to deep lilac-blue, with darker blue and white markings and a yellow crest. Though short, the exquisite flowers show up remarkably well among the dwarf iris leaves. There are selections with dark blue or white flowers also with a yellow crest. This perennial makes a fine little ground cover—it spreads slowly but steadily, running along the ground with small creeping rhizomes. After it finishes blooming, it remains a tidy but dense forest of miniature iris leaves.
This dainty-looking yet rugged plant is equally happy in part to light shade; the more sun it gets, the more soil moisture it needs. Crested iris is a charming plant to place amid other wildflowers or beneath shrubs in a more formal mixed border. Try it too at the edge of a perennial border for late-spring color. It also deserves a spot in shady rock gardens.
ZONES: 3–9
BLOOM TIME: Spring
LIGHT: Part shade
HEIGHT: 4–8 inches
INTEREST: Delightful blue flowers on short plants; arching, soft, green leaves like large blades of grass