The Plant That Always Returns

See this empty pot in front of our house. It looks this way twice a year - but only for a little while. In the winter it freezes, and in the summer it burns up. We put temporary flowering plants in it until the real occupant returns again, and it always returns. Last winter after a deeper than usual freeze in our valley, my husband was sure that it would not return, but it did. I have no idea what kind of plant this is. We bought it at a nursery many years ago. The pot is really in bad shape. If we tried to move it even a little, it would fall apart, but the plant comes back each time more beautiful than ever and so we just keep the old pot.