A perennial herb, found as an apparent native on sea-cliffs, predominantly on chalk and limestone but also on other base-rich substrates. It is most frequent on bare cliff edges, but also grows in maritime grassland and in quarries inland. Elsewhere it is a casual garden escape in waste places and on roadsides. Lowland.
B. oleracea was first recorded in Britain in 1548. On sea-cliffs it is impossible to distinguish native from alien populations and all are mapped as if they are native. These coastal plants are var. oleracea; other varieties and cultivars occur as casuals.
Suboceanic Southern-temperate element.
Count of 10km squares in Great Britain: 98
Count of 10km squares in Ireland: 0
Count of 10km squares in the Channel Isles: 1
Atlas Change Index: 0.9
Scarce Atlas Account
NOTE: The account below is for the sub-species. Closely related species and sub-species may have separate accounts listed elsewhere in the Online New Atlas
Brassica oleracea L. var. oleracea
B. oleracea is found on maritime cliffs, most often on calcareous substrates, but also on base-rich sandstones, shales, and less commonly on clay. It often behaves as a chasmophyte, but competes well in grassland and mixed herb communities at the top or base of the cliff, although it is usually less long-lived here. It is typically found near centres of human population, and often does not persist on unpopulated coastlines. Associated species include Armeria maritima, Cochlearia officinalis, Daucus carota, Plantago coronopus, Raphanus raphanistrum subsp. maritimus, Silene uniflora and Tripleurospermum maritimum.
B. oleracea var. oleracea is a relatively short-lived (rarely to 20 years) evergreen perennial without means of vegetative multiplication. It forms woody trunks with annual groups of leaf-scars by which it can be aged. There is a range of pollinators, especially bees and hoverflies, and it is fully self-incompatible; the Tynemouth population contains in excess of 20 sporophytic S-alleles. Up to 100,000 seeds are produced per plant (more commonly about 10,000). Seeds germinate best at 20°C in a long day, after dark chilling. Viability scarcely drops after 4 years storage.
Many southern populations seem to be fairly stable and are not threatened. The species is not very hardy, and suffers after very severe winters. In some areas, fluctuating populations may be reinforced by introductions from cultivated plants in gardens and allotments.
Outside Britain, B. oleracea var. oleracea is found on Heligoland and locally on the Channel and Atlantic coasts of France. Subsp. robertiana (Gay) Rouy & Fouc. occurs in France, Italy, Corsica, Sardinia and Yugoslavia. B. oleracea sensu lato is also recorded as an introduction in North America and Australasia.
B. oleracea has long been known in Britain, where it was first found on Dover cliffs by W. Turner in 1548. Mitchell (1976) and Mitchell & Richards (1979) argue that B. oleracea is not native in northern Europe, but was introduced, probably by the Romans, and has been able to persist in a feral state on seacliffs. However, in many areas it may be maintained by reintroductions which morphologically soon revert to ‘wild’ phenotypes. As the distinction between ‘native’ and ‘introduced’ is therefore meaningless for maritime populations, all established coastal colonies are mapped as if they were native.
A. J. Richards
PLANTATT - Attributes of British and Irish plants. (.zip 1455KB) This dataset was compiled and published in 2004, and last updated in November 2008. Download includes an Excel spreadsheet of the attributes, and a PDF explaining the background and nomenclature. Note that the PDF version is the booklet as published, whereas the Excel spreadsheet incorporates subsequent corrections. A hardcopy can be purchased from the Centre for Ecology and Hydrology.
Atlas text references
Jalas & Suominen (1996)
1965. Vergleichende Chorologie der zentraleuropäischen Flora. Volume 1. 2 vols.
1979. Biological Flora of the British Isles. No. 145. Brassica oleracea L. ssp. oleracea. Journal of Ecology. 67:1087-1096.
1991. Crucifers of Great Britain and Ireland. Botanical Society of the British Isles Handbook no. 6.
1994. Scarce plants in Britain.
2000. Domestication of plants in the Old World, edn 3.