The flower of Conophytum marginatum subsp. marginatum emerges from the mouth formed by the slit between the paired leaves, as a long white tube topped with pinkish purple petals. The flat top of each cylindrical, fused leaf-pair has a round perimeter seen from above. A slit through the leaf top centre indicates the vertical channel from which the flower can appear. When not flowering, this sign of the existence of two leaves, rather than one, is rather small.

Halfway up the white flower tube the coloured sepal tips are visible. The sepals form a tube enveloping the longer petals that are also erect, white and attached to each other until a point higher up where they split into the spreading, coloured tips of the salver-shaped corolla top around the stamens and styles. The yellow anthers protrude in this species (Smith, et al, 1998).