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 nigromontana, commonly known as Swartberg Satin, is a rare South African endemic species found in the Western Cape province occurring in the Groot Swartberg Mountains. It is found along streams in shade at around 1800 meters in elevation, flowering near the end of summer in January and February. Growing from 10 to 16 cm high, it has leaves that lie flat on the ground and blue-purple almost pink flowers with a short tube. Unlike most other Geissorhiza species, plants often produce small corms along the base of the stem.