Kadua laxiflora, a member of the Rubiaceae (coffee) family, has smooth, usually erect stems 30 to 60 cm (1 to 2 ft) long that are woody at the base and four-angled or -winged. The leaves are opposite, thin in texture, elliptic to sometimes lance-shaped, and 8 to 18 cm (3 to 7 in) long and 2.5 to 6.5 cm (1 to 2.6 in) wide. Stipules (leaf-like appendages), which are attached to the slightly winged leaf stalks where they join and clasp the stem, are triangular, 5 to 14 mm (0.2 to 0.6 in) long with a point 4 to 11 mm (0.2 to 0.4 in) long. Flowers are arranged in loose clusters up to 30 cm (1 ft) long at the ends of the stems and are either bisexual or female. The green hypanthium is top-shaped, 1 to 1.5 mm (0.05 in) long, with sepals 1.5 to 3 mm (0.06 to 0.1 in) long and1 to 2 mm (0.04 to 0.08 in) wide at the top. The greenish-white, fleshy petals are fused into a trumpet-shaped tube in 5 to 14 mm (0.2 to 0.6) long. Capsules are top-shaped and 2 to 3 mm (0.08 to 0.1 in) long and 3 to 4 mm (0.1 in) in diameter.