Sand vine is a perennial, vigorous, aggressive climber covering fences and shrubs. Flowers are in round clusters on stalks from the leaf axils. Flowers white, tiny, strongly scented; the corolla lobes stand upright around a fleshy corona. Blooms July–September. Leaves heart-shaped to triangular, opposite, to 3 inches long. Unlike many other milkweeds, sand vine has clear, watery (not milky) sap. Fruit a large, tapering pod, circular in cross-section (not angled or ridged) (sand vine has confusingly been called angle-pod in the past); seeds are attached to tufts of white, silky hairs and are released in late winter or early spring.
Similar species: Other Missouri milkweed vines have milky sap. Angle-pod (Gonolobus suberosus), found mostly in the Bootheel, has oval leaves with heart-shaped bases, angled (ridged) pods, and yellowish flowers with spreading corolla lobes. Our 2 climbing milkweeds in genus Matelea resemble angle-pod vegetatively, but the pods are covered with slender, warty projections (not angled).