Horticultural selection with white flowers of the circumpolar arctic-alpine perennial from the Caryophyllaceae family. Individuals with white flowers exist spontaneously in some natural populations, but the name 'Alba' refers to a form selected and maintained in cultivation for the consistency of this coloration.
The habit and general behavior are identical to those of the type species: a dense, tight cushion of bright green, formed of tiny linear and ciliated leaves interlocked in compact rosettes, not exceeding 2 to 4 cm in height. Growth remains very slow.
The flowers, set directly on the surface of the cushion, have five petals of pure white to slightly creamy white at the center, with stamens bearing conspicuous yellowish anthers that slightly warm the heart of the flower. The calyx, barely tinged green, contrasts sharply with the characteristic purplish-red of the type form, giving this selection a fresher and brighter appearance.
In cultivation, its flowering occurs in May-June.
The growing conditions are the same as for the type species: perfect drainage, lean and mineral soil, full sun, and protection against stagnant winter moisture. It is particularly advantageous when cultivated in an alpine trough or rock crevice, where the contrast between the dark green cushion and the white flowers is fully highlighted.