Perennial of the Campanulaceae family, native to southern Italy, mainly from the Gargano promontory in Apulia from which it takes its name, as well as western Greece. It naturally grows in limestone cliff crevices, sunny rocky escarpments, and old walls, at low and medium altitudes, in a Mediterranean to sub-Mediterranean context.
It forms spreading and semi-trailing clumps, 10 to 15 cm in height, with a very branched habit that spreads widely over rocky surfaces. The leaves are small, kidney-shaped to heart-shaped, crenate, of a medium green, arranged on slender and flexible stems that intertwine in a dense mass.
The star-shaped flowers, of a bright lilac-blue with a well-marked white center, are produced in remarkable quantity and cover the plant to the point of almost entirely masking the foliage in full bloom. This carpet of small blue stars floating on a compact cushion is the immediate visual signature of the species.
In its natural habitat, its flowering extends from May to July. In cultivation, it can start as early as April-May and continue intermittently until summer.
It requires a calcareous or neutral soil, very well-drained, in full sun exposure. Hardy and undemanding once established, it is perfectly suited to sunny rock gardens, walls, and raised planters.