There are about 267 species of Wahlenbergia worldwide, of which most are found in South Africa. Most of them are annuals or herbaceous perennials with bell-shaped flowers in shades of mauve, blue, white, or cream.

Wahlenbergia capensis, synonymously known as Campanula capensis and commonly known as Cape Bluebell, is a South African endemic erect annual herb, up to 50 cm tall. Its showy blue flowers start appearing from early spring, decorating the sandy flats and lower mountain slopes of the Cape Floristic Region.