Passiflora incarnata aka Purple Passionflower

Passiflora incarnata is a vine that lives for many years. Its names include maypop and purple passionflower. It belongs to the passionflower family, called Passifloraceae. It is native to central and eastern America and Bermuda. It grows in sandy thickets, fields, and open ground. It also grows in moist woods. Its stems grow fast and use tendrils to climb. These cling to nearby plants or garden supports. The vine can also trail along the ground and still flower.

Garden height ranges from about 5–8 feet [1.5–2.5 metres]. Reports give a spread of 1.6–6 feet [0.5–1.83 metres]. Its reach also depends on the support it climbs. Roots send up shoots that can cover much larger areas. Stems stay woody where winters are warm. Cold winters kill the top growth back to the ground. Leaves grow in turn along the green stems. Each leaf has three deep lobes and toothed edges. The tops are dark, while the undersides are paler. Two glands sit on each leaf stalk. Leaves may turn yellow in fall.

The flowers have a scent and pale petals and sepals. These sit around a purple crown. Fine threads, called filaments, give the crown its fringed look. Sources report flower widths of about 2.5–5 inches. Bloom may run from May into October. The time of bloom depends on where the vine grows. Each flower lasts about one day. Egg-shaped berries form through summer and turn yellow as they ripen. These maypops hold many brown seeds but rather little pulp. People can eat ripe fruit fresh or cook it into jelly. Birds and mammals also eat the fruit. The flowers supply nectar. The young of several butterfly species feed on the leaves.

Grow this vine in sun or partial shade with good drainage. Full sun gives the best flowering. It accepts sand, loam, and clay across a broad pH range. It does well in moist soil. Once plants take root, they can cope with drought. Loose mulch helps keep roots cool. Missouri Botanical Garden lists USDA zones 5–9. It warns that plants may die in zone 5. Florida guidance gives a warmer range that extends through zone 11. The RHS rates it H6. The vine can climb trellises, fences, and arbors.

Roots can spread with force, and wet winter soil can cause rot. Mites, scale, whitefly, viruses, and honey fungus may occur. Nematodes can cause serious damage. Caterpillars eat the leaves. The plant also burns readily. Past use as medicine does not prove safe home use. One food source lists leaves and flowers as safe to eat. NC State warns that leaves contain cyanogenic glycosides. Eating them can make you vomit or feel drowsy. They can also cause an uneven heartbeat. Herbal preparations may also strengthen the effects of alcohol and sedatives.