Brassica oleracea var acephala, is a different species from Chinese kale, B. oleracea var alboglabra, but the two plants have several features in common. Both are rather coarse and strongly flavoured in comparison with the more delicate cabbages of their respective regions; both have tough stems and are good only when young.
Kale and cabbage are varieties of the same species, and both are descended from the same wild ancestor. Kale is the more primitive of the two, and was the ordinary greenstuff of country people in most parts of Europe until the end of the Middle Ages, when the ‘headed’ cabbages were bred. In England kale was known as cole or colewort. Kale (or kail) is the Scottish name, and its continued prevalence is significant. Kale can grow in hard climates where the more delicate cabbages cannot, and still remains in common use in northern regions. There was even a ‘Kailyard school’ of Scottish writers, of whom J. M. Barrie was one. They were so called because they described Scottish rural life and a kailyard (kale field) was a typical feature of this. Indeed, the word ‘kail’ became generic for ‘dinner’ in Scotland; thus the ‘kail bells’ were those which chimed at dinner time, whether or not kail was on the menu.
Other names for kale include the Dutch boerenkool (farmer's cabbage) and ‘collards’ (a corruption of colewort and the usual name in the USA). All derive from the Greek kaulos, meaning stem. An interesting passage in Bradley (1736) illustrates the original primacy of the word ‘cole’. He says that the Greek word ‘Brassica’ is ‘in English Cole and Colewort’, and refers to ‘the sort of Cole which makes an Head, which we call Cabbage’, and to ‘the Cole so remarkable for its Flower, which we call Cole-Flower, or more commonly Cauly-Flower’. He continues:
The Coleworts are of many Kinds, some of which have their Leaves beautifully cut and curl'd of various Colours, such as Reds of all Sorts, Purples, Yellows and Greens, and also White. I have seen a Bed of these as beautiful as ever I saw any Thing of the Garden.
One advantage which kale had over cabbage until recently was that the season of some varieties extended over the January to April period when there was no cabbage. Hence the name Hungry Gap which one variety has.
Curly-leafed kales such as Scottish kale (Scotch kale in the USA) are less coarse and rigid than the plain kinds, and it is they which are still popular as food. The others are now grown mainly for animal feed.
In the USA the principal kale-growing states are Virginia, Maryland, and New Jersey.
Rape kale belongs to two different species: Brassica napus (rape and colza); and B. rapa ssp campestris (Indian rape and Indian colza). Common names are applied in accordance with the uses to which the plants are put: rape usually for cattle feed, and colza for oil from its seed. (The name colza comes from the Dutch kool zad, meaning kale seed.)
The Tuscan variety, cavolo nero or black kale, has lately become popular beyond its homeland, perhaps because of its ease of cultivation and extreme hardiness, while remaining toothsome.
Seakale belongs to a different genus. Seakale beet, along with other sugar beets and chards, belongs to the spinach family. Both resemble true kale in having thick, tough stems and in needing to be well cooked.
Alan Davidson was a distinguished author and publisher, and one of the world's best-known writers on fish and fish cookery. In 1975 he retired early from the diplomatic service—after serving in, among other places, Washington, Egypt, Tunisia, and Laos, where he was British Ambassador—to pursue a fruitful second career as a food historian and food writer extraordinaire. Among his popular books are Seafood of South-East Asia, North Atlantic Seafood, and Mediterranean Seafood. In 2003, shortly before his death, he was awarded the Erasmus Prize for his contribution to European culture.
Bradley, Richard (1736), The Country Housewife and Lady's Director, Parts I and II, facsimile of 6th edn in one vol, London: Prospect Books (1980).
