Gather berries from the plant during the winter. These berries have seeds in them and will be needed for propagation.
Remove the fruit from the seed. Clean the seeds with water and a fine strainer.
Store the seeds in a cool, dry place until spring. Keep the seeds separated, and store them in moist sand, in a cellar, basement or refrigerator.
Turn the seeds in the sand at least once per week throughout the rest of the winter.
Plant the seeds early in the spring in a prepared garden bed.