Passionfruits come from passionflower vines (Passiflora). The most common species grown for its fruit is P. edulis. It is hardy only to Zone 10. You may find it at your local garden center or from a specialty fruit nursery. Other species that produce delicious fruit include banana passionfruit (P. mollissima), hardy to Zone 7, giant granadilla (P. quadrangularis), and P. ligularis (said to have the best-tasting fruit of any passionflower). All passionflowers prefer full sun and well-drained soil. They do well in poor soils. If the soil is too rich or you fertilize the vines too often, they'll put on lots of rampant leafy growth at the expense of blooms and fruits. Provide them with a sturdy support, such as a pergola. Some of the larger passionflower species can grow more than 50 feet long. That makes for a heavy plant, especially when the leaves are wet after a rainstorm.