Although several varieties of passion vine bear fruit, the most common variety grown in the United States is the native maypop (Passiflora incarnate), which bears an egg-shaped edible fruit. It grows wild from Florida to Pennsylvania and west to Kansas. The maypop is suitable for planting in U.S. Department of Agriculture plant hardiness zones 7 through 11.
Passion vine is an aggressive vine often seen growing on fences, trellises and trees in its native region. In the fall, when the orange or yellow fruit ripens, it may appear the egg-shaped fruit is growing on the tree the passion vine uses for support. The leaves are dark green and have three lobes. The outstanding feature of the passion vine are the flowers borne all summer long. The filaments radiating from the corona of the purple or white-petaled flowers are distinctive and elaborate. The flowers last one day and are followed by the fruit that appears in the fall.
The passion vine grows in full sun to part-shade in deep well-drained soil such as sandy loam. It does not grow well in heavy clay or waterlogged soils. It can be grown in the ground almost anywhere in their native range. In colder areas, or where the soil is unsuitable, passion vines are grown in large containers. Passion vines die to the ground in freezing temperatures, but revive in the spring. Passion vines require support of at least 6 feet tall and wide. A 2- to 3-inch layer of mulch around the root zone helps conserve moisture and protect the roots during the winter. Plant passion vine in a permanent location at the same level it is planted in its container. Passion vines do not transplant well as the extensive root system is easily damaged.
The native passion vine is a relatively care-free plant. Growth slows dramatically in dry conditions, so supplemental moisture keeps the plant vibrant during the summer months. After the first hard frost, when the top of the plant dies, clear away all dead plant material and cut the vine back to the ground. Fast-acting chemical fertilizer can kill a passion vine. The best way to fertilize a passion vine is by adding a 1-inch layer of well-rotted compost around the roots in spring after the vine begins to emerge from the ground.
Passion vine fruit can be eaten fresh, preserved or used in a variety of dishes. The fruit is ripe and sweetest when it turns orange and falls from the plant. Passion fruit has a woody taste if picked directly off the plant.