Crambe is a genus of roughly 30–40 annual and perennial flowering plants in the mustard family, Brassicaceae (order Brassicales). Plants in this genus are native to a broad range spanning Europe, Turkey, southwest and central Asia, and eastern Africa, growing in habitats from coastal cliffs and shingle beaches to dry grasslands and rocky slopes.
Morphologically, crambes are characterised by large, sometimes glaucous basal leaves and erect flowering stems, typically leafless or nearly so above the base, that bear dense racemes of small white or (less commonly) yellow four-petalled flowers. The fruit is a distinctive two-segmented silicle: the lower segment is stalk-like and sterile, while the upper segment is rounded and contains a single seed — an unusual structure among the crucifers that gives the genus taxonomic distinction within the family.
The genus was formally described by Linnaeus and published in Species Plantarum in 1753. Among the most familiar species is Crambe maritima (sea kale), a coastal perennial of European Atlantic and Baltic shorelines long cultivated as a vegetable; its blanched young shoots were a prized delicacy in British and French cuisine. Crambe cordifolia, native to the Caucasus, is widely grown as an ornamental for its billowing clouds of tiny white flowers rising on branched stems up to 2 metres tall. Crambe hispanica subsp. abyssinica (Ethiopian mustard) has received commercial attention as an industrial oilseed crop: its seed oil is rich in erucic acid and has properties similar to whale oil, making it a candidate for industrial lubricants and bio-based chemicals.
Crambe species also play a minor ecological role as larval food plants for certain insects, including the weevil Lixus canescens and some Lepidoptera such as the lime-speck pug (Eupithecia centaureata).
Etymology
The name Crambe reaches English through Latin crambe, itself borrowed from the Ancient Greek κράμβη (krambē), which denoted a kind of cabbage. The connection reflects the genus's membership in the cabbage family (Brassicaceae) and the superficial resemblance of some species' large leaves to those of brassica vegetables.
Distribution
Crambe species are distributed across Europe (particularly Atlantic and Mediterranean coasts), Turkey, southwest and central Asia, and eastern Africa. Individual species occupy diverse habitats including coastal shingle and cliffs, dry grasslands, steppes, and rocky hillsides. The centre of diversity is broadly the Mediterranean basin and the Caucasus region.
Cultivation
Crambe maritima (sea kale) has a long history of cultivation as a vegetable in western Europe; young shoots are traditionally blanched to reduce bitterness. Crambe cordifolia is grown as an ornamental perennial valued for its large basal foliage and clouds of small white flowers. Crambe hispanica subsp. abyssinica is cultivated as an industrial oilseed crop in parts of Europe and East Africa, primarily for its erucic-acid-rich seed oil.
Taxonomy Notes
Crambe was described by Linnaeus and published in Species Plantarum (1753). It belongs to the tribe Brassiceae within the family Brassicaceae, order Brassicales. The genus is distinguished from close relatives by its two-segmented fruit (a silicle with a sterile lower joint and a seed-bearing upper joint). GBIF's backbone dataset recognises approximately 71 accepted names at species and infraspecific rank within the genus.
