Passion flower vine, also known by its Latin name, Passiflora, is a perennial vine grown for its large, ornamental flowers, climbing growth habit and in some species, edible fruit. Legend says that passion flower was named by a Jesuit priest who saw similarities between the flower of the plant and the crucifixion. The plant blooms during summer and early fall, producing numerous flowers in shades of red, purple, white and blue. Native to most temperate regions of the world, passion flower vine requires warm temperatures to grow and flower. In the United States, gardeners typically grow the vine indoors.
Keep passion flower vine in a location that receives at least four hours of direct sunlight each day, such as a north or east-facing window. Maintain a temperature of 54 to 65 degrees Fahrenheit during spring, summer and fall, and about 50 degrees Fahrenheit during winter to encourage a resting period.
Water passion flower vine once per week from March to August to keep the soil evenly moist. Reduce the watering frequency to once every 10 to 14 days from August until February to allow the soil to dry slightly between applications.
Feed once every two weeks during spring, summer and fall using a balanced 20-20-20 NPK fertilizer. Use a fertilizer with added micro-nutrients if possible to further promote growth and flowering. Apply according to the manufacturer's instructions for the best results.
Re-pot passion flower vine once every two years during late winter or early spring, just before new growth begins. Increase the size of the container by about 2 inches and provide a fresh, well-drained potting soil. Keep the plant in a shady location for one week after re-potting to allow time for recuperation, and then transfer back into the original location.
Prune the vine during early spring each year and about two weeks prior to re-potting to improve appearance, growth habit and flowering. Use pruning shears to cut each vine back to about 6 to 8 inches from the soil.