Star-shape, blue-purple flowers decorate blue-eyed grass in spring and early summer. A wonderful plant for edging a walkway or the front of a cottage garden border, this compact perennial grows in a slowly spreading clump. Although “grass” is in its name, blue-eyed grass is actually in the iris family. Its sturdy leaves remain green and upright throughout the growing season.
Blue-eyed grass complements a host of perennials. Plant it at the base of clematis as an easy-care groundcover. Partner it with New Zealand flax and enjoy the distinct textures of both plants' straplike leaves. Blue-eyed grass also pairs well with all types of roses; both plants grow well in rich, well-drained soil.
Blue-Eyed Grass Care Must-Knows
An easy-to-grow plant, blue-eyed grass thrives in full sun or part shade and moist, well-drained soil. It produces a thick stand of healthy, dark green foliage when planted in soil that is rich in organic matter. Prior to planting, enrich the planting area with well-decomposed compost, mixing it into the soil in the planting hole and the surrounding area.
Plant nursery-grown transplants 18 to 24 inches apart in early spring. Water plants regularly through the first growing season to promote a strong root system. Blanket the soil around plants with a 2-inch-thick layer of mulch to prevent soil moisture loss.
You may want to cut blue-eyed grass back to the ground after blooming has ended to prevent unwanted self-seeding. Plants may need to be divided every few years in early spring to maintain vigorous growth. Blue-eyed grass tolerates division and replanting well.
More Varieties of Blue-Eyed Grass
'Aunt May' Blue-Eyed Grass
Sisyrinchium striatum is a clump-former with clean gray green iris-like leaves striped with cream. The pale yellow flowers cluster on 20-inch-tall zig-zag stems. Zones 7-8
Common Sisyrinchium angustifolium forms clumps of grassy foot-long leaves. Its winged and branched stems carry small clusters of bright blue flowers, yellow at the throat. Each lasts a single day but there is a succession. Self-seeds freely. Zones 5-8
Blue-Eyed Grass Companion Plants
Lupine draws the eye skyward with its gorgeously colored and interestingly structured flower spikes. Bicolor Russell hybrids are the most popular type. Their large pea-like flowers come in amazing colors and combinations, clustered in long spikes on sturdy stems. Lupine prefers light, well-drained soil that is slightly acidic, and it does not tolerate heat or humidity well. It performs best in areas with cool summers, especially the Pacific Northwest.
One of the longest bloomers in the garden, hardy geranium bears little flowers for months at a time. It produces jewel-tone, saucer-shape flowers, and mounds of handsome, lobed foliage. It needs full sun, but otherwise it is a tough and reliable plant, thriving in a wide assortment of soils. Many of the best are hybrids. Perennial geraniums may form large colonies.
Named for the Greek goddess of the rainbow, iris indeed comes in a rainbow of colors and in many heights. All have the classic, impossibly intricate flowers. The flowers are constructed with three upright "standard" petals and three drooping "fall" petals, which are often different colors. The falls may be "bearded" or not. Some cultivars bloom a second time in late summer. Some species prefer alkaline soil while others prefer acidic soil.
Play up the blue hues in the garden by pairing blue-eyed grass with the blue-green foliage of rue.
Count on this sage to bloom through summer, when blue-eyed grass is taking a flower break.
Yarrow's yellow flowers and silver-gray foliage are a lovely contrast to blue-eyed grass.