Plumbago zeylanica is a sprawling shrub with 0.5–2.5 meters long stems. The leaves are simple and alternate, well-developed on flowering stems, with ovate blades ranging from 3–12.5 cm long and 2–5 cm wide. The leaf apex is acute to acuminate, and the base is rounded to broadly cuneate, with glabrous surfaces and entire margins. Petioles are 0.3–1.5 cm long with an auriculate base, and stipules are absent. The flowers are arranged in racemes 6–30 cm long, with a stipitate-glandular rachis and small bracts. The bisexual flowers are actinomorphic (radially symmetric), featuring a tubular, 5-lobed calyx with dark green ribs and densely stipitate glands. The corolla has five white salverform petals with a slender 18–23 mm long tube and obovate lobes 6–7 mm long. There are five distinct stamens opposite the petals, with blue or purple dithecal anthers that open by longitudinal slits. The ovary is superior with five 1-celled carpels, one anatropous ovule on an elongate funiculus, and a deeply 5-lobed glabrous style. The fruit is a membranous, oblong capsule, approximately 4–5 mm long, glabrous, and circumscissile near the base, enclosed by the calyx and corolla. Each fruit contains one dark purplish-brown seed about 4 mm long. It grows in arid, disturbed areas such as dunes, dry forests, and shrublands between 0-610 meters.