SuperCal petunias are annuals. Typically, an annual is a plant that does not live from year to year; but, if you live in a mild climate, there are steps you can take that may help your SuperCal survive until the next Spring:
Bring the plants inside, if possible. If you can uproot them carefully and place them in pots and containers, that would be best. Trim them back and place the pots next to windows that get a lot of sun. If you cannot remove them from the ground, trim them back and cover them with a tarp during the night until the sun is out and they can get some warmth.