Greek trachelos — neck, referring to the use of the plant in the treatment of tracheal ailments.

Erect perennial herbs with woody rootstocks. Leaves alternate, simple. Flowers in flat-topped clusters, occasionally solitary. Calyx and corolla tubular with prominent protruding styles. Fruit capsule splitting towards the base, closed at the tip.

T. caeruleum is used as a perennial border plant and cut flower.

Seed or softwood cuttings.

Flowers small, in dense, flat-topped clusters; fruits closed at the tip. The protruding styles and clustered flowers are reminiscent of Centranthus ruber.

7 species from the Mediterranean.

Source: Spencer, R. (2002). Campanulaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.