The specific epithet medium means that this plant has intermediate characteristics in respect of other species of the genus Campanula.

The basal leaves are stalked and lanceolate to elliptical and 12–15 cm (5–6 in) long with serrated leaf edge.

These attractive bell-shaped flowers are short-stalked, large and hermaphroditic, with different shades of violet-blue or rarely white.

It grows on stony, rocky and bushy slopes, at an altitude of 0–1,500 metres (0–4,921 ft) above sea level.

It prefers cool or warm zones; not suitable for the tropics or hot, dry regions.