Not a grass, Blue-eyed Grass actually is in the Iris family, but it has grass-like leaves that are semi-evergreen.  The leaves stand up and fan out like those of an iris, but they're narrower.
 
     It has star-shaped blue-violet flowers with sunny yellow centers that bloom profusely in late spring to early summer.  The flowers open in the morning and close at sunset.
 
     Blue-eyed Grass spreads by underground rhizomes and works well along pathways and borders.  It's easy to control and keep neat looking, and it makes for lovely cut-flower arrangements.  Butterflies, bees and songbirds are attracted to this plant.
 
     Blue-eyed Grass is a good substitute for non-native liriope.
 
     Fun fact: Native Americans cooked and ate the greens.