Arenaria aggregata

Perennial of the Caryophyllaceae family, Arenaria aggregata is an Iberian and southwestern European species, present in the Spanish sierras, southern France, and northern Morocco. It occupies open lawns, rock gardens, and screes of the montane and subalpine levels, on well-drained calcareous or siliceous substrates, generally between 1,000 and 2,500 meters of altitude.

It forms rounded and dense cushions, distinctly domed, reaching 20 to 30 cm in height and spreading over 30 to 50 cm in diameter. The foliage is composed of linear-lanceolate, rigid leaves, of a bright green, tightly packed in small rosettes that give the cushion a regular texture and prickly feel to the touch.

The flowers are white, with five well-developed petals, slightly star-shaped, carried on short peduncles that barely emerge above the foliage. Their number, at the time of full bloom, is such that they almost entirely cover the surface of the cushion. In its natural habitat, flowering extends from June to August depending on the altitude. In cultivation, it generally occurs in May-June.

It requires a mineral substrate, very well-drained, in full sun, and tolerates summer drought well once established. Hardy and relatively easy to grow in rock gardens or troughs.