blue-eyed grass

blue-eyed grass, (genus Sisyrinchium), genus of the more than 75 species of perennial grasslike plants of the iris family (Iridaceae) native to the Americas and the Caribbean. Despite their common name, the plants are not true grasses. They bear starry, yellow, white, or blue to violet flowers with six petallike segments and wiry, fibrous rootstalks.

Common blue-eyed grass (Sisyrinchium angustifolium), from North America and the West Indies, has been naturalized in parts of Europe. The plant has tall (50-centimetre [20-inch]) flower stems that bear 2-centimetre (about 1-inch) yellow-eyed blooms. Western blue-eyed grass (S. bellum) extends from western Mexico to Oregon and has flowers that range in colour from blue to purple. Blue pigroot (S. micranthum) is found throughout South and Central America and parts of Mexico and has naturalized elsewhere. Another South American species, the pale yellow-eyed grass, or Argentine blue-eyed grass (S. striatum), bears a spike up to 90 cm (35 inches) tall with clusters of creamy white blooms.