Superbells are a patented plant marketed the Proven Winners company. It was developed by Japanese botanists who, after lots of breeding combinations with the African plant Calibrachoa, came up with the hybrid known as Superbells. It looks like a type of petunia with its miniature blossoms, but is actually genetically a different plant. Unfortunately, patented plants are illegal to propagate. However, you can save the seeds that form from pollinated blossoms. The offspring that grows from the seeds will not be the same as the plant you have now.
Collect the dried seed pods late in the morning after the dew has had a chance to dry. Pinch them off, or use a pair of scissors. Place the pods in a bowl so any small seeds that escape from the pod will collect at the bottom.
Break open the seed pods and remove the seeds, letting them fall to the bottom of the bowl. Since the seeds are so tiny, you might not be able to get all of them out of the husk.
Place the sieve over a clean, dry bowl. Pour the seeds and any remaining hulls into the sieve. Shake the sieve gently to force the seeds to fall into the bowl. Any remaining husk material will be sifted out and can be thrown away.
Transfer the tiny seeds into a small plastic bag that seals or a small coin envelope. Push them in with your fingers, as they are too small to be picked up with a spoon. Seal the container.
Label the envelope or bag. Include the name of the flower--Superbells--the color of the blossoms, and the date of the next growing season. Store it in a cool and dark place until it is time for spring planting.