The 2–9 m tall Hexalobus monopetalus is a deciduous shrub or small, crooked tree with a scattered spreading canopy. It has a slender, twisted stem with low branches that range in colour from brown to black and are covered in light brown hair. The leaves of this wonderful tree have a petiole up to 4 mm long, and the leaf blades are 36-175 x 12-65 mm, leathery, glossy green, obovate, with visible venation on both surfaces. The tops of the leaves have long, obscure lateral veins and brown hairs that are evident along the midrib.

The flowers are found either singly or in groups of 2 or 3, on very short stalks (subsessile), in the axils of the leaves, on leafless twigs or sometimes from the trunk, and emerge when the plant is without leaves. The flowers are made up of 3 sepals and 6 petals. The sepals are brown on the outside, 4-7 mm long and enclose the petals until the flower opens. The petals are pale yellow, greenish or cream, fused at the base forming a short tube, up to 4 mm long, with 6 narrowly lance-shaped lobes 12-22 mm long, that appear crumpled or wrinkled when the flower is open. These 6 fused petal lobes are a key characteristic which has given this tree its scientific name. Hexalobus monopetalus blooms in spring (August and September) and produces edible fruits that ripen in late summer, from January to April. These fruits are 15-50 x 10-25 mm, cylindrical to obovoid, sometimes constricted between the seeds, scarlet when ripe. They can be harvested before they are fully developed on the tree, although they are typically picked at that time to allow for further ripening. The pulp of the ripened fruit is bright yellow and has a sweet, pleasant acidic flavour.