Moonflower

Native to tropical and subtropical regions of the Americas, from the southern United States through Mexico, Central America, the Caribbean, and tropical South America to Argentina. Now naturalized in tropical regions worldwide, particularly in Southeast Asia and the Pacific Islands. Found at elevations from sea level to approximately 1,500 meters in moist, disturbed habitats, forest edges, and along stream banks.

Stems:
• Twining, herbaceous, smooth or sparsely hairy, robust and fast-growing, 3-10 m long
• Green to reddish-green, with milky sap

Leaves:
• Large, heart-shaped to ovate, 10-20 cm long and 8-15 cm wide
• Dark green, smooth, with prominent palmate venation
• Long petioles, 5-15 cm

Flowers:
• Spectacular funnel-shaped corolla, 10-15 cm across when fully open
• Pure white, sometimes with faint greenish tube, intensely fragrant with jasmine-like scent
• Opening rapidly at dusk in approximately 1-2 minutes (anthesis), closing by morning
• Borne singly or in clusters of 2-3 at leaf axils
• Calyx of 5 sepals, 2-3 cm, with distinctive reflexed bracts beneath

Fruit:
• Globose capsule, 2-3 cm diameter, covered with small prickles
• Contains 2-4 large seeds, 8-10 mm, dark brown to black, densely hairy

Habitat:
• Fast-growing perennial vine in the tropics (USDA zones 10-12), typically grown as an annual in temperate regions
• Found in forest edges, disturbed areas, stream banks, and roadsides in its native range
• Flowers are timed to nocturnal moth pollinators, especially large sphinx moths (Sphingidae)
• The white color and intense fragrance are specifically adapted to attract night-flying insects

Pollination:
• Primary pollinators are sphinx moths with long proboscises that match the deep nectar tube
• Flowers reflect moonlight, appearing to glow in the dark, enhancing visibility to nocturnal visitors
• Nectar production peaks at midnight
• Flowers are open for only a single night

Adaptations:
• Rapid flower opening (1-2 minutes) triggered by falling light levels and rising humidity
• Seeds contain ergot alkaloids similar to morning glory, which deter seed predation
• Twining growth allows rapid ascent into canopy for maximum flower display

Sow seeds directly after last frost; nick seed coat with a file and soak overnight in warm water to improve germination to 70-80%. Plant in full sun in warm, fertile, well-drained soil. Provide a sturdy trellis, fence, or arbor as the vine is vigorous and heavy. Space plants 20-30 cm apart. Spectacular when trained over a pergola near a patio where the evening fragrance can be enjoyed. Avoid excessive nitrogen which promotes foliage over flowers. Water regularly but do not overwater. Collect seeds from dried pods in fall. Can be started indoors 4-6 weeks before last frost for earlier bloom. Hardy as an annual in USDA zones 3-11.