Sometimes passion fruit seeds germinate themselves. If you live in a windward area of Hawaii or another warm, moist area, when passion fruit becomes overly ripe and falls to the ground, its seeds sometimes grow into a new plant without any help from you. But if you want to start more plants of this tart, delicious vining fruit, you can easily do it by scooping the seeds out of a fruit and starting them in controlled conditions, away from bugs, snails and slugs.
Scoop seeds out of an overly ripe, shriveled passion fruit and then rinse them with cool water to remove as much pulp as possible.
Scarify seeds by rubbing each one with fine sandpaper. According to Purdue University, scarification is more effective than soaking the seeds in water.
Fill several small nursery pots or a flat with standard potting soil and then sprinkle the soil with water until the water runs out the drainage holes. Make planting holes with a pencil or screwdriver ½ to 1 inch deep and then insert one passion fruit seed into each hole and cover with soil. Keep your pots or flat in a sunny area and also keep your soil moist.
Transplant your seedlings when they are about 10 inches tall to a sunny location near a wall, building or other means of support. You can also provide a trellis for this rambling vine.