The snake’s head or widow iris is putting on a show of flower at the back of the Rock Garden.
Iris tuberosa (syn. Hermodactylus tuberosa) is a scented member of the genus Iris. The flowers are typical of the genus in their form, bearing three inner tepals (referred to as standards), and three outer tepals, or falls, though are striking in their dusky green and black colouring. The slender, grass-like foliage grows to approximately 50cm, and is slightly taller than the flower stems. This is a creeping species with finger-like tubers. It is wide ranging in its distribution, occurring from France to Greece, the Balkans, Turkey and Israel, where it occurs naturally in scrub and on banks and hillsides. In cultivation I. tuberosa grows well given full sun and good drainage in beds and borders, and it naturalises in long grass, and grows particularly well in dry, chalky soils. The genus Iris is widespread throughout the northern hemisphere, and comprises over 300 species of bulbous, rhizomatous or tuberous perennials, many of which are cultivated for their ornamental value.