Huernia loeseneriana flowers are bell-shaped to funnel-shaped. The corolla tubes, about 2 cm long, widen gradually into five spreading, triangular lobes, their tips long and attenuating.
Flower colour is beige to pale creamy yellow, sometimes referred to as dirty yellow, with maroon spots, often becoming elongated into transversal lines across the lobes. Fleshy papillae are present in parts of the corolla inner surface, visible in the photo. There is a yellow margin around the corolla, while the lobe tips have some accentuated maroon colouring in the flower of the photo.
The secondary corolla lobes, small pointed protrusions in mid-lobe, are conspicuous in flowers of this plant. The outer corona inside the base of the corolla consists of five black velvety lobes, thick and ascending in the flower throat. The inner corona (in the centre of the outer one and over the staminal column), has tiny red-purple, erect lobes, their tips diverging.
The flower is without the prominent ring or annulus found around the coronas of some other Huernia flowers, like H. zebrina subsp. insigniflora, H. transvaalensis or H. zebrina.
The H. loeseneriana flower resembles that of H. longituba, its shape also reminding of others, for instance H. leachii. H. longituba does not always have four-angled stems and the its corolla markings are always spots, not lines.
Flowering of H. loeseneriana occurs from late spring to mid-autumn (Germishuizen and Fabian, 1982; Hardy and Fabian, 1992; White and Sloane, 1937).