Hermodactylus tuberosus

Hermodactylus tuberosus, sometimes called the widow iris or snake's head iris because of its dark colouring, is a Mediterranean plant with a finger-like tuberous rhizome similar to that of an iris. Fine, four-angled leaves accompany iris-like flowers from late winter onward, yellowish green with almost velvety blackish-brown veining on the falls. It grows in full sun, well-drained, calcareous soil, and needs a dry summer rest, as the rhizome dislikes standing moisture.