Passiflora incarnata alba

Passiflora incarnata alba is the rare pure white form of the native maypop, the wild passionflower of the American Southeast. The flower keeps all the improbable structure of the species, an intricate three-inch bloom with a fringed corona above a central column of stamens and styles, but drained of every trace of lavender: white petals, white sepals, and a white corona, luminous and cool against the deep green foliage. The effect is a ghostly, refined version of a familiar roadside wildflower.

This selection is a Woodlanders introduction, a rare pure white-flowered maypop shared with us many years ago by our friend Gene Cline, a Georgia native-plant pioneer and expert. Passing a plant like this one from garden to garden is exactly the sort of quiet conservation that keeps an uncommon native form in cultivation, and growing the white maypop carries that small stewardship forward.

Like the species, the white maypop climbs by curling tendrils or sprawls across open ground, hosts the caterpillars of the Gulf fritillary and other passion-vine butterflies, and ripens the same lime-sized, egg-shaped fruit, green turning leathery yellow, with sweet-tart, aromatic pulp around dark seeds. Bees and butterflies work the summer flowers, and songbirds take the fallen fruit.

Grow the white maypop on a fence, a trellis, or a mailbox post in full sun and sandy, well-drained soil, and give the roots room, since the vine runs by root into a generous colony. From about zone 7 the top dies back each winter and returns from the root in late spring, so treat the plant as a fast, flowering perennial where frost is sharp. Site where the cool white flowers can be read at close range, since they glow at dusk when the lavender forms have gone to shadow.