Sub-shrub of the Linaceae family, this subspecies is endemic to the Pyrenees, where it occupies scree, rocky areas, and rock crevices, mainly on siliceous or mixed substrates, between 1,500 and 2,800 meters in altitude. It is distinctly different from the type subspecies due to its adaptation to the montane and subalpine levels, as well as its marked affinity for acidic terrains, whereas Linum suffruticosum s.s. rather seeks limestone.
The habit is more flexible and less rigidly hemispherical than that of the type species: the stems, woody at the base, spread and lengthen between the stones, following the relief of the rocky substrate. The foliage remains narrow, acicular, dense, and bright green, but the flowering stems are more slender and more loosely branched.
The flowers, pure white to slightly pinkish white, have five broad petals delicately veined with pink-lilac from a pink to purplish center; the buds are pink, adding an extra touch of color to the bloom. This delicate pink veining on a white background is one of the most endearing features of this subspecies. In its natural habitat, its flowering extends from July to August depending on the altitude.
In cultivation, it requires a very well-drained mineral soil, preferably slightly acidic to neutral, in full sun, without excess stagnant winter moisture. It naturally integrates into alpine rockeries and mountain gardens.