Adventive. Herb with stems long and creeping, rooting at nodes, thick and climbing. Leaf petioles erect, channelled in lower part with sheath forming narrow wing. Lamina 3-lobed with a smaller lobe from near base of lateral ones, i.e. sub-digitate. Leaf with terminal lobe 18 x 9.5 cm, elliptic-ovate; all lobes dark green with pale green bands above along midrib and veins. ± climbing if suitable host close. When climbing the leaves are usually 5-7-lobed and are uniformly dark green above. Plant sterile.