Plants herbaceous. Stems prost-rate, climbing, or erect, glabrous. Leaves petiolate (to 1.5 cm) or sessile; blade ovate, lance-elliptic, or spatulate to oblanceolate, (3–)5–9(–15) × (1–)2.5–4(–7) cm, base attenuate, apex acute, acuminate, or obtuse. Inflorescences 3–15(–30) cm, rachises glandular, viscid; floral bracts lanceolate, 3–7 × 1–2 mm. Flowers heterostylous; calyx 7–11(–13) mm, tube glabrous but with stalked glands along length of ribs; corolla white, 17–33 mm, tube 12.5–28 mm (less than 2 times length of calyx), lobes 5–12 × 3–3.5 mm; stamens included. Capsules 7.5–8 mm. Seeds reddish brown to dark brown, 5–6 mm.
Plumbago zeylanica and P. scandens, both Linnaean species, have heretofore been treated as distinct, the former name applied exclusively to Old World plants, the latter to New World specimens. John Edmondson (pers. comm.) indicates that he believes this “could be a classic case of New World and Old World taxonomists each doing their own thing.” Plants in herbaria under these two names appear indistinguishable.
