Passiflora is a genus in the Passifloraceae family, containing several hundred species of mainly evergreen, climbing, tropical vines. Grow passiflora species for their showy flowers and sweet, pulpy fruit known as passion fruit. Passiflora vines are best suited to tropical climates, but species with limited frost tolerance are available.
Passiflora species are tendril-climbing vines with green foliage and flowerheads made up of 5 to 10 open-flat, arching or bowl-shaped tepals (sepal and petal fusion) and prominent stamens and ovaries, often arranged in a three-pronged formation, lending a star-burst appearance. Flower colors range from pale yellow and pink to red and purple. Passiflora plant height and spread varies by species and also depends on the structure it climbs on.
Establish passiflora vines on trellises, arbors and fences for their showy flowers and fruit (depending on species--Passiflora alatocaerulea, for example, does not form fruit). Choose native species where possible because passiflora vines have the potential to become invasive. In areas like South Florida, Passiflora foetida has become invasive and is spreading, according to University of Florida Extension. Passiflora vines attract butterflies and hummingbirds.
Passiflora species like a warm climate in full or part-sun locations, with deep, moist, organic and nutrient-rich, well-drained soil. Prune vines in spring, removing any frost-damaged vegetation, but avoid cutting to the main stem. Water newly planted passiflora vines daily, and water once a week after establishment.
Passiflora caerulea blooms with white to pale violet flowers with purple centers on 10- to 30-foot vines. Grow P. caerulea in USDA zones 7 through 11. Passiflora incarnata blooms reach about 6 feet in height with a 4-foot spread, and are hardy in zones 7 through 10. Passiflora quadrangularis flowers from mid-summer to autumn on a 15- to 30-foot vine and is less frost-tolerant. Grow this vine in zones 10 through 12. Passiflora racemosa has red flowers and grows in zones 10 through 12.
Pests of passiflora vines include nematodes and caterpillars. Hand-picking removal of caterpillars is one remedy, or choose homemade or commercially available insecticidal soap for insect control. Reduce nematode populations with proper soil preparation: solarization (covering the soil with plastic for several weeks before planting), organic compost and selection of nematode resistant, healthy plant specimens from reputable nurseries and garden centers. Your local county extension office is a good source of information regarding plant problems and control particular to your area.