Kentucky Old Fashioned Petunia is a mix of clear tones of rose, burgundy, purple, and light and dark lavender fragrant flowers, including bi color, on sprawling plants that bloom all season until frost. Self-sows, but you will get earlier flowers by starting the seeds indoors. Much reward for little effort.
I grew these back in 2005 or 2004 and there were plenty of flowers, but weirdly they were all white. Maybe I didn't plant enough. Haven't tried them again.