Sisyrinchium micranthum, commonly known as blue pigroot or striped rush-leaf, is a grass-like species in the iris family, Iridaceae. It is native to Mexico, Central America, and South America and widely naturalised elsewhere. The white to cream flowers are between 10 and 20 mm in diameter and have blue to purple centres. These are followed by rounded 3 to 8 mm brown capsules that enclose the dark brown seeds.