Obovate or oblanceolate leaves, about 4-17 per plant, form a basal rosette around the compressed stem.

This species generally has one to ten scapes and cymose inflorescences that are 4–18 cm long.

S. rotundifolium's wide, sporadic distribution ranges from the Kimberley region in Western Australia east to northeastern Queensland with a significant population near Taroom, Queensland.

Its typical habitats include damp sandy soils on creekbanks, receding waterholes, or Melaleuca woodlands.

Bean noted that the description of S. irriguum matched that of S. rotundifolium except for the flower color (pink with red highlights for S. rotundifolium and pale yellow to white for S. irriguum) and capsule size, which both fall within the natural variation for this species.