Gladiolus tristis bears large, cream coloured, pale yellow or greenish yellow flowers, often marked by brown-shaded longitudinal bands on the tepal midlines. In the photo such bands of a purplish colour, each bisected by a thin white vein, are seen on the upper three tepals only.
The tube varies in length from 4 cm to 6,5 cm. The funnel or trumpet shape of the corolla opens widely, displaying pale beige, oblong anthers and a white style. Faint spicy fragrance suffuses the air around the young flowers in the evening.
The flowering season varies, often from late winter to midsummer, although in some areas the flowers are seen in autumn (Manning, 2009; Goldblatt and Manning, 1998; iNaturalist; www.pacificbulbsociety.org).