Hesperantha coccinea (River Lily or Crimson Flag) is a flowering plant in the family Iridaceae, native to South Africa and Zimbabwe. It is never far away from water and at the Edinburgh Garden is found close to cascading water in the Rock Garden. It is a herbaceous perennial plant growing to 60cm tall with slender lanceolate leaves up to 40cm long and 1cm broad. The flowers are red, pink or white.
It is cultivated as an ornamental plant in gardens for its attractive flowers and is popular with florists. It is sometimes used in Christmas floral decorations because of its late flowering habit.