Harvest very ripe fruit or collect seeds from fallen ripe fruit.
Rinse the pulpy flesh from seeds under cool running water and allow seeds to air dry for several hours before you plant them.
Fill a nursery flat with standard potting soil and water it thoroughly until the water runs from the drainage holes.
Make holes 1 inch deep and 2 to 3 inches apart, using a pencil, screwdriver or the tip of a pointed trowel.
Drop one seed into each hole and cover it with additional potting soil. Water the seeded flat again and then insert it into a clear plastic bag. Close the bag with a rubber band or twist tie.
Keep the flat in an area with filtered sunlight where the temperature is moderately warm; do not expose planted seeds to temperatures lower than about 65 degrees Fahrenheit or higher than 90 degrees.
Remove the flat from the plastic bag once or twice a week to water it.
Remove the plastic bag when you see green shoots emerging from the soil surface.