Geissorhiza is a large genus of around 84 perennial species, of small to medium corm bearing plants in the Iridaceae family found in the winter rainfall region of the south and west coasts of southern Africa. Many of them make very handsome container plants and benefit from extra water during growth. The name Geissorhiza is derived from the Greek words geisson and rhiza which mean tile and root respectively. This is in reference to a tunic which covers the corms like a roof tile. The bulb-like structure is used as a storage organ during the dormant period. It is closely related to the genus Hesperantha, the main difference being that most Hesperantha are night bloomers.

Geissorhiza bolusii, synonymously known as Geissorhiza dregei and Geissorhiza rupestris, is a South African endemic species that grows on damp shady, sandstone slopes in moss in the Western Cape. It grows from 3 to 10 cm high and has white flowers in a two to eight flowered spike. Leaves are lanceolate to ovate with the lower ones usually prostrate. This species blooms from mid-spring to early summer during the months from October to January.