Renegade petunia. I have all purple petunias, but recently this pink one came up.
Volunteer verbena. I have all red verbena, but these pink and purple ones came up.
I suspect that in both cases they grew from flowers I had last year that seeded. They showed up rather late in the season. I guess they needed the extra time to grow from seeds, while the ones I planted probably were nurtured in greenhouses earlier in the season.