Calostemma is a small genus from Australia belonging to the Amaryllidaceae and this is the only wholly endemic Australian genus in this family. It comprises just two species, as far as I know, one yellow, one purple. Reports of white flowered species (alba and scott-sellickiana) refer to the related but distinct genus Proiphys.
Both species bloom in autumn and the flowers are borne in an umbel of six to eighteen blooms on a leafless stem, 20-50 cm high. Flower colour is either pure yellow or purplish red according to species. Both have a floral tube paler than the petals, both have yellow anthers. Each trumpet-shaped flower is held on a long, thin pedicel and is about 2 cm long.
It flowers best after dry periods so should be allowed to dry off after the leaves yellow. Growth is improved by the application of slow released fertiliser. Seeds germinate on the plants and should be sown in a well-drained mix, placed in a warm spot and protected from snails and slugs.
Order from Spring and Autumn lists.