The dark yellow to ochre-orange flowers of Lasiosiphon deserticola grow in clusters from three to six at stem-tips, a whorl of involucral leaves around their bases.

The narrow, cylindrical calyx tube is about 15 mm long. The five, sometimes four, oblong calyx lobes spread from 6 mm to 10 mm in diameter, their margins rolled under and the lobes variably curving.

There are no petals, but five small, membranous, petal-like scales are visible protruding from the flower mouth. Such petal scales are common in flowers of the Thymelaeaceae family.

Two rows of stamens reside inside the tube, the filaments shorter than the anthers and the upper row of stamens near or among the scales and larger than them. The ovary is small, the style shorter than the calyx tube.

The flowers are strongly fragrant at night, suggesting moth participation in their pollination. Flowering may happen all year round, more in winter and spring, rain possibly a trigger (Vlok and Schutte-Vlok, 2015; Manning, 2009; Shearing and Van Heerden, 2008; Manning and Goldblatt, 1997; Bond and Goldblatt, 1984; iNaturalist; JSTOR; http://pza.sanbi.org).