Gladiolus is the largest genus in the Iridaceae family with around 255 species. They are perennial bulbous flowering plants, sometimes called Sword lilies, but usually by its generic name, Gladiolus. It has been studied by taxonomists and now includes the genera Acidanthera, Homoglossum, Anomalesia and Oenostachys. The geographic range includes Africa, Madagascar, Europe, and the Middle East. They are treasured the world over for their beautiful, showy flowers which grow on tall spikes. These plants are often planted in cut flower gardens or in the back along the border, as they grow 60cm to 1.8 m tall. They make excellent cut flowers and are easily grown in raised garden beds and rockeries. Most Gladioli do equally well in pots. Gladioli are the flowers associated with a fortieth wedding anniversary.

Gladiolus subcaeruleus is a rare South African endemic species found between Caledon and Bredasdorp in the Western Cape province where it grows on sandy loam and clay slopes. The flowers are produced in autumn. It is described as having pale blue to mauve flowers with yellow transverse to spear shaped markings outlined in purple on the lower tepals. The dorsal tepal is hooded over the stamens.