Iris may be rhizomatous or bulbous perennials, with narrowly leaves and erect stems bearing flowers with 3 large spreading or pendent fall petals, alternating with 3 erect, often smaller, standard petals, in late winter, spring or early summer
Tall Bearded irises are herbaceous rhizomatous perennials to 70cm or more, with flowers 10-20cm across, bearded on the falls, in late spring and early summer
'Thornbird' is a clump-forming perennial to 1m in height, with up to 6 flowers per stem, the standards a very pale greenish-yellow with a faint purple margin, the falls a greyed green with blotches of violet near the margin; beard gingery yellow