Sea kale
Crambe maritima
Botanical family: Brassicaceae
Crambe maritima forms a large bluish perennial rosette, waxy fleshy leaves, an impressive habit. In the wild: maritime pebbles and sands of the Channel, North Sea, Brittany, Normandy coasts. Historic English harvest technique: cover the shoots in spring with an opaque cloche for 4-6 weeks, harvest the white etiolated shoots. A tender, mild, slightly hazelnut taste, between asparagus and cabbage. Traditionally served with roast beef in high British cooking.
Sun to partial shade
Very well-drained, sandy or stony, tolerates salt and chalk
Moderate, self-sufficient once settled in
Excellent (-25 °C), perennial 10-15 years
Overwinters in your zone
Insect-pollinated (white flowers in clusters May-June, very nectar-rich)
Role in permaculture
A perennial cabbage of the Channel-Atlantic coasts practically vanished from our cooking, yet the marine vegetable par excellence, grown in England from the 18th century in 'blanching pots' to produce tender, delicate etiolated shoots. One planting, 10 to 15 years of production. Hardy, sparing in water and fertiliser, little prone to disease, one of the most generous vegetables of the seaside permaculture garden or in warm draining soil.
Good companions
Attract pollinators and beneficial insects
Poor companions
Same family: shared diseases and pests
Insects attracted or useful
Seasons & availability
A coastal perennial sown from March to May; once the plant is established, after at least a year, the young shoots are forced under an opaque cloche in late winter and cut blanched, from February to April.
Available: February, March, April.
Guidance for the oceanic / temperate climate; it may vary with your region, altitude, exposure and growing method.
Sources
- La Ferme de Sainte Marthe, « Réussir la culture de la crambe maritime » (fermedesaintemarthe.com/en/blogs/comment-reussir-la-culture-de/reussir-la-culture-de-la-crambe-maritime)
- Plants For A Future, « Crambe maritima » (pfaf.org/user/Plant.aspx?LatinName=Crambe+maritima)
Nutritional & medicinal properties
For educational purposes. Not a substitute for medical advice. Effects depend on the form, the dose and personal context.
Precautions & contraindications
A protected species on the coastline of several French regions (Brittany, Normandy, Pays-de-la-Loire): wild picking is forbidden there, and one must obtain seeds or plants through the specialised horticultural trade. No toxicity known in normal food use. Like all cabbages, it contains glucosinolates, with a potential goitrogenic effect only at a massive dose, in case of extreme iodine deficiency (a very rare case): to be included within a varied diet.
Family behaviour: Brassicaceae
In general, Brassicaceae produce glucosinolates, sulphur compounds with a mild biocidal effect on the soil (a biofumigant effect, sometimes sought between two sensitive crops). Members of the cabbage and mustard family, they are prone to the cabbage white and clubroot.
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Species & varieties
The best-known species and varieties in France.
Common varieties
Voices of peoples
Paraphrases attributed to their documented sources. Never an invented quote.
British horticultural tradition of the 18th–19th centuries · English coasts, cottage gardens
English gardeners discovered in the 18th century that sea kale, gathered on the shingle of the Sussex coast and planted in the kitchen garden, can be 'forced' under clay bells. The white shoots obtained, tender, melting, fragrant, became a sought-after dish of the high Victorian table, served with the Sunday roast beef. The practice disappears in the 20th century with market-gardening industrialisation, but the sea kale waits in the old gardens.
Maud Grieve, A Modern Herbal, 1931 ; John Wright, Edible Seashore (River Cottage Handbook), 2009 ; Conservatoire Botanique National de Brest, fiche Crambe maritima.
Regulatory status in Europe
A species' status varies from one country to another: check before growing, selling or foraging it outside France.
FranceProtected species
A species protected throughout metropolitan France: uprooting, gathering and destruction in the wild are prohibited. Cultivation from legally sourced seeds or plants remains permitted.
Arrêté du 20 janvier 1982 (modifié) fixant la liste des espèces végétales protégées sur l'ensemble du territoire national
Before you forage
This plant is often gathered from the wild. Only pick what is abundant, never a protected species, and never uproot a whole plant (roots) without the landowner's permission. Rules vary by country and region, check locally.