The rock milk apricot is an evergreen, multistemmed, densely branched, scrambling shrub, 1-2 m high or a lean, intertwining climber in which case it reaches heights of up to 5 m. The young branches and growth points are covered with soft, reddish brown hairs. The bark is reddish brown to greyish brown. All parts of the plant contain milky, rubbery latex.

The simple, opposite leaves are characteristically carried upright. They are leathery are oblong to broadly elliptic, 20-60 x 12-25 mm in dimension, dark green above and paler below and have pronounced herringbone veins on both sides.

The flower tube and segments are pinkish to reddish orange to white on the outside and brilliant white on the inside. The flowers are large and up to 30 mm wide, borne in dense, showy clusters at the tips of branches, and are sweetly scented.

The fruit are rounded to pear-shaped and 35-50 mm in diameter. They are dark green to lime-green when young, turning yellow to orange as they mature. The skin is somewhat fleshy and velvety and tough, but peels away easily. Inside are numerous seeds, varying from round to almost bean-like and embedded in the sweet-sour pulp. The fruit resembles the apricot in colour but the taste is certainly different - the flesh is tasty and slightly sour, especially close to the seed.