Hibiscus genevii is a bush that can reach up to 2-3 meters in height. The adult leaves are ranging from 4 to 7 cm in length by 3 to 5 cm in width.
The leaf is elliptical, rather rounded at the tip and at the base. The leaf margin is entire, sometimes rather crenate on the half distal part. A glandular is also visible near the midvein on the lower leaf surface. The petiole is 1 to 4.5 cm in length, quite canaliculated and hairy on the upper surface. Stipules are 2-3 mm long, fleshy and deciduous in nature. Flowers are solitary with long pedicels of the order of 4-9 cm. The corolla can reach up to 12 cm with 5 petals spread out that can reach a length of 6-8 cm and pink-purple in colour with a red centre. The epicalyx has 8 to 9 linear teeth that are virtually free and between 1 and 1.4 cm in length. The calyx has a campanulated, rather smooth tube measuring between 1.5 and 2.5 cm, with deltoid lobes that can be as long as 1.2 cm. The staminal column is 5-8 cm long. The style is longer than the staminal column by some 5 mm and is divided into 5 long branches of more or less 7 mm. The stigma is pale red with a capsule of 2 to 2.5 cm. The ovary consist or more or less 10 ovules. The grains are rather oval, measure 4.5 mm in length are greyish in colour.