Crocosmia


Crocosmia, montbretia, is a small genus of flowering plants in the iris family, Iridaceae. It is native to the grasslands of southern and eastern Africa, ranging from South Africa to Sudan. One species is endemic to Madagascar.

Description

They can be evergreen or deciduous perennials that grow from basal underground corms. The alternate leaves are cauline and ensiform. The blades are parallel-veined. The margin is entire. The corms form in vertical chains with the youngest at the top and oldest and largest buried most deeply in the soil. The roots of the lowermost corm in a chain are contractile roots and drag the corm deeper into the ground where conditions allow. The chains of corms are fragile and easily separated, a quality that has enabled some species to become invasive and difficult to control in the garden.
They have colourful inflorescences of 4 to 20 vivid red and orange subopposite flowers on a divaricately branched stem. The terminal inflorescence can have the form of a cyme or a raceme. These flower from early summer well into fall. The flowers are sessile on a flexuose arched spike. The fertile flowers are hermaphroditic. All stamens have an equal length. The style branches are apically forked. They are pollinated by insects, birds or by the wind. The dehiscent capsules are shorter than they are wide.
The alternative name montbretia is still widely used. The genus name is derived from the Greek words krokos, meaning "saffron", and osme, meaning "odor" – from the dried leaves emitting a strong smell like that of saffron – when immersed in hot water.

Species

Species accepted by World Checklist of Selected Plant Families
Crocosmias are grown worldwide, and more than 400 cultivars have been produced. Some hybrids have become invasive, especially C. × crocosmiiflora hybrids, which are invasive in the UK, New Zealand, the American Pacific Northwest, and probably elsewhere.
Crocosmia are winter-hardy in temperate regions. They can be propagated through division, removing offsets from the corm in spring.
The following cultivars have gained the Royal Horticultural Society's Award of Garden Merit:
Other cultivars include: