The White Lady Stonebreaker

Habit: Perennial herbaceous plant developing flowering stems 20–60 cm tall. Stems: Woody at the base, erect or elegantly arching, generally glabrous and characterised by a typical reddish colour. Leaves: The basal leaves are gathered in dense cushion-forming rosettes. They are linear or spatulate, very narrow and elongated (2–8 cm), with a leathery texture. Along the margin they show small white dots: these are calcium carbonate secretions produced by specialised glands, which solidify and create calcareous incrustations. Along the flowering stem the leaves become progressively smaller, reducing in the upper part to simple linear bracts. Flowers: Gathered in a large dense and branched panicle that may bear hundreds of flowers, often distributed on one side of the stem only. Each flower has a glabrous calyx with 5 lobes and a corolla composed of 5 white spatulate petals. The petals often show minute purplish dots toward the centre. Fruits: A septicidal capsule of obovoid shape containing numerous fusiform seeds, adapted to wind dispersal among rock crevices. Flowering: April–June.

Chorological type: Southwestern European orophyte. Distribution in Italy: Present along almost the whole Apennine chain and in the major islands; absent from the Po plain, from much of the eastern Alpine arc (Valle d’Aosta, Lombardy, Veneto, Trentino-Alto Adige, and Friuli-Venezia Giulia), and from Puglia. Habitat: An excellent pioneer species, specialised in colonising vertical cliffs, rock walls, and crevices in exclusively calcareous rocks, between 1000 and 2500 m a.s.l.

Generic name (Saxifraga): From the Latin saxum (rock) and frango (I break). The name “stone-breaker” is due both to the biological ability of the plant to settle in rock crevices and to the ancient belief, based on the doctrine of signatures, that it was a remedy against kidney stones. Specific name (callosa): Refers to the texture of the leaves, which have a scarious and callous surface because of superficial calcareous incrustations.

Southern saxifrage is regarded as a medicinal species in folk tradition. In the past, fresh leaves were crushed and applied locally to treat boils, minor skin infections, and eye inflammations. Herbal teas with astringent properties were also prepared from it. Besides its botanical and medicinal interest, the plant is much appreciated in alpine gardening for its ability to create spectacular cascading white blooms on the rocky walls of rock gardens.