Iris

Iris is a hardy herbaceous perennials. It is a wide-ranging genus of more than 200 species, native to the temperate regions of the northern hemisphere. There are several identifiable groups of the beardless (without a tuft of hairs on the 3 lower petals) irises and their hybrids, including the Louisiana irises from southeastern USA, the Pacific Coast irises from the west side of North America, and the Eurasian Spuria and Siberian irises. Growing conditions vary greatly, but mostly they are very frost hardy and prefer a sunny position; some of the beardless types like very moist soil. Propagate irises by division in late summer after flowering or from seed in fall; named cultivars by division only.

 

It is considered poisonous and contains a component that is toxic to humans and livestock.  The fresh root may cause nausea and eye irritation, headaches, and inflamed throat. (Foster & Duke, p. 223).

However, the seeds can be used like coffee (Foster & Duke, p. 223).

 

The juice of the fresh roots of Iris, bruised with wine, has been employed as a strong purge of great efficiency in dropsy. Iris roots are also used to treat skin diseases. The fresh root of the Iris germanica is a powerful cathartic, and for this reason its juice has been employed in dropsy. It is chiefly used in the dry state, being said to be good for complaints of the lungs, for coughs and hoarseness, but is now more valued for the pleasantness of its violet-like perfume than for any other use. Iris flowers are used as a liver purge. (The Flower Expert)

The roots were poulticed for swelling, sores, and to releive pain and inflammation.  A decoction of the root was used to cause vomiting and for treating blood or liver disorders (Foster & Duke, p. 223).