One of the prettiest, if not the most showy, of spring flowers is the widow iris or black iris – Iris tuberosa. Until recently this was called Hermodactylis tuberosus but it is, as far as I know, properly called Iris tuberosa at the moment, although how long that will be is anyone’s guess. The flowers are obviously iris shaped but there are some differences, most noticeably the lack of ‘standards’, the tepals that usually stand erect in iris flowers. The rootstocks are odd too, being long, finger-like tubers that spread horizontally under the soil surface.
This sun-loving perennial from the Mediterranean region is easy enough to grow as long as the soil is well drained but it can be difficult to place in the garden because it forms a scruffy clump of narrow leaves about 60cm high that often flop at flowering time. The flowers are carried singly on stems 45cm high and, because the leaves have often flopped by this time the flowers often sit upright on slanting stems. So this is not the best plant for a showy garden but it is an interesting plant nonetheless. And the flowers are attractive, unusual and lightly fragrant so are worth growing if only for cutting.
The common names all come from the unusual and sombre colouring although the mix of green and blend of brown and purple is not quite black. The dullness of the blooms is leavened somewhat by the green style arms that sit over the falls. It is quite at home in the rock garden if there is room and it can naturalise in grass if it is not too vigorous. It is perhaps best planted next to a small deciduous shrub such as a chaenomeles or small spraea where the branches can help support the flower stems without casting too much shade.