A long established rock plant which is near enough herbaceous and emerges in early spring with tiny shoots which expand to produce the dense mats of green foliage. This is quite small but covers the ground very well. Each leaf is approximately 1 cm long or so and slightly serrated. Flowers are very attractive and a purplish/blue colour, bell-shaped and produced in rapid succession. Flowering period is mainly in early summer although sporadic flowering continues throughout summer.