Crambe maritima - Sea Kale

The Crambe maritima, also known as Sea kale or Sea cabbage, is a wild and perennial cousin of the biennial cabbage found in our vegetable gardens. This cabbage is a unique plant that adds beauty to gardens and can also be eaten. It thrives in rocky or sandy soil that is well-drained but still fresh. The plant has beautiful bluish-grey curly foliage and abundant ivory-white flowers in spring that are pleasantly fragrant. It's a wonderful addition to any garden and is easy to care for.

Sea kale is a long-lasting plant that is commonly found in Western Europe, from Sweden and Russia to Portugal via France. It can be spotted growing naturally on the pebbly beaches of Normandy, and occasionally in the sands and gravels of the coasts of the English Channel and the Atlantic Ocean. Nowadays, it is strictly protected due to its natural habitat being threatened.

The plant thrives in a sunny location, cool maritime climate, and rocky soil that is basic (chalky) with no organic matter, but rich in mineral elements. Sea kale is part of the Brassicaceae family, formerly known as the Cruciferae. It can survive very low temperatures as low as -20°C (-1°F), and it's easy to grow in well-drained soil in gardens.

Overall, sea kale is a hardy plant that can live for over 20 years. It belongs to the cabbage family and needs a specific type of environment to grow. Its importance lies in being a protected species that adds diversity to the natural landscapes of Western Europe.

The Crambe maritima develops from a thick and woody base from which crumpled and violet young shoots emerge that unfold into large round and fleshy leaves, very undulated at the edges, covered with a bluish bloom. An old clump can reach 60 cm (24in) in height when flowering (40 cm (16in) for foliage), with a spread at least equivalent. The young leaves are edible, especially when "blanched" by sheltering them from light with a mulch or a clay bell. This pretty vegetation remains evergreen in winter. The plant blooms from May to July, depending on the climate, generously. Numerous floral stems emerge from the foliage clump. They bear a few small leaves at the base and branch out into panicles at their ends. Each rather dense panicle is adorned with white to pinkish flowers with 4 petals, rather large and pleasantly fragrant. This flowering with a sweet honey fragrance, rich in nectar, attracts many pollinating insects. It gives way to globose and yellowish fruits called siliques, containing seeds that can be harvested and easily sown in March-April after a period of cold for 2 to 3 months.

In the kitchen:

All parts of the Crambe maritima are edible; their flavour is slightly different from that of garden cabbage. The leaves should be consumed before flowering occurs, and the flower buds can be eaten raw or cooked. The blanched young shoots (petioles) are used in English cuisine, their delicate flavour resembling both cardoon and asparagus. The roots, rich in starch and sugar, can be cooked and eaten.

In the garden:

The Crambe maritima is a star plant with moist soil for a sunny rock garden. Plant it among a few large stones in a gravel bed where it will be the only one visible in winter. Its strong personality does not prevent it from mingling in mixed borders with ground cover roses, perennial or shrubby salvias, daylilies, and Darley heathers. In a more rustic style, it can accompany Armeria maritima, onagras (Oenothera macrocarpa or versicolor), Echinops, catmints, hollyhocks or even beautiful grasses such as Muhlenbergia capillaris, Pennisetum aleupecuroides and Stipa tenuifolia. Quite accommodating, the sea kale is spectacular in fertile and fresh garden soil like the vegetable garden, but it often ages less well there.