Thunbergia Laurifolia in 6″ Pot

A fast-growing, perennial herbaceous twining climber (liana) with a tuberous root system; can reach 6–15 m (20–50 ft) or more on supports. Stems are slender, twining, mostly hairless. Leaves are opposite, glossy green, lanceolate to triangular-ovate, 13–20 × 4–10 cm (5–8 × 1.5–4 in), with an acuminate tip, truncate to cordate base, margins subentire to sparsely toothed; 3–5 main veins; young growth glabrous (distinguishing it from the hairier T. grandiflora). Flowers are borne in pendulous racemes up to 30 cm long. Each flower is trumpet-shaped, unscented: short broad tube whitish outside, yellowish inside; the limb flares 5–7 cm across with 5 (sometimes 6–7) overlapping lobes, pale blue to mauve/lavender (one lobe often larger). Blooms almost year-round in the tropics; individual flowers open in the morning and drop by evening. Fruit is a subglobose capsule (∼13–15 mm) with a long beak (25–30 mm), containing 2–4 seeds.

Quick care: full sun to light shade (best flowering in ≥6 hrs sun; tolerates semi-shade). Prefers rich, moist, well-drained loam with organic matter; tolerates sandy/clay if drainage is good. Water regularly—keep evenly moist, especially in heat; mature plants are vigorous but dislike waterlogging. Warm, humid climate; frost-tender (hardy USDA 9b–11; protect below ∼5 °C/40 °F). Feed monthly with balanced fertilizer during growth; mulch to keep roots cool. Provide sturdy support (trellis, arbor, fence, pergola); prune hard after flowering to control size and encourage branching. Propagate by stem cuttings or by division of tuberous roots. Generally pest-free; watch for spider mites, aphids, whitefly in dry conditions. Can become invasive—dispose of prunings carefully; listed as an exotic weed in some tropical countries. Medicinally used in Thai traditional medicine (Rang Jeud tea) for detoxifying; leaves have antioxidant/anti-inflammatory compounds.