The white or creamy white flowers of Lacomucinaea lineata, previously Thesium lineatum are borne solitary from leaf axils or at nodes on the upper stems where the leaves may have dropped off already. Flowers are small, cup-shaped with five pointed, spreading petal lobes, the anthers exserted. Flowering happens in spring and summer after rain.

The white, ellipsoid, fleshy fruits that follow become 1 cm long. These buds were seen near Oudtshoorn in April (Vlok and Schutte-Vlok, 2010; iSpot).