Collection of perennials for coastal borders

The collection consists of:

- x 1 Sea Thrift or Sea Pink 'Alba': a small plant forming a cushion of fine green leaves even in winter, topped with small umbels of white flowers from May to July. This perennial does not exceed 20 cm high, but it spreads on the ground. Perfect for bordering flower beds or rockeries.

- x 1 Sea Holly: a botanical species from coastal areas, forming an upright, 60 cm high tuft, with persistent, bluish-green, cut, tough, and very spiny foliage. From June to September, this thistle produces round, remarkable metallic blue flower heads.

- x 1 Sea Lavatera or Spanish Mallow: a fast-growing but short-lived woody perennial with an upright, bushy habit reaching 1.50 m high and 1 m wide. It has persistent, velvety, beautiful ash-green foliage and 4 cm cup-shaped, bicoloured flowers in white, washed with lilac pink, with a magenta centre from June to October.

- x 1 Sea Kale: a cousin of our vegetable kale that is cultivated as much for its edible young shoots as for its beauty. This plant reaches 60 cm high when flowering and 50 cm wide. It forms a tuft of superb curly, bluish-green leaves with white, cloudy, fragrant flowers between May and July.

Each of these perennial plants appreciates the sun and the conditions of the seaside. With a lesser or greater degree of resistant to frost and drought, they will thrive particularly well in sandy, rather poor soils that do not retain too much moisture in winter. Limestone is well tolerated. They can compose the basic structure of a rockery: place the Sea Thrift, Sea Holly, and Sea Kale in the front, and the Sea Lavatera in the background. To allow these three plants to fully flourish, keep a distance of 60 to 80 cm between each one. Ideally, plant them between large stones. The Sea Lavatera is the least frost-resistant (to -7 °C at its peak) and it does not live more than 5 years, but it can be easily propagated by cuttings and seeds.

Grow these coastal perennials with other species that appreciate the same environments: rockroses, lavenders, Corsican spurge, Globularia trichosantha, or Senecio mandraliscae. You can create very decorative scenes in rocky flower beds and gravel beds.