Alyssum loiseleurii

Perennial of the Brassicaceae family, endemic to the Atlantic coast of southwestern France, strictly localized to the maritime sands of the Landes and Pyrénées-Atlantiques. It constitutes one of the few alyssums confined to coastal dune environments in France and represents a remarkable heritage element of the flora of the Gascon coastline.

It forms a prostrate and dense carpet, with woody stems at the base, brown and creeping, bearing small oval gray-green leaves, slightly fleshy. The flowering, from May to June, is abundant and spectacular: the short and compact clusters are covered with bright yellow flowers with four petals, almost entirely masking the foliage. The whole forms a very spread-out cushion, about ten centimeters high, remarkably flowered. Also known under the synonym Alyssum arenarium Loisel., it is sometimes confused with other alyssums of similar habit.

Rare and localized species, weakened by tourist traffic and artificial dune stabilization, it benefits from protection statuses in its distribution area. In cultivation, it requires a sandy, very well-drained soil, in full sun, and poorly tolerates stagnant moisture. It is suitable for sand gardens, light rockeries, and coastal gardens of Atlantic inspiration.