These are Petunia. The upper group are called Double Lavender Madness while the lower group are called Double Blue Madness. My dad-in-law bought these flowers and I plant some of them by the stairs. Aren't they lovely?
Petunia is a trumpet shaped, widely-cultivated genus of flowering plants of South American origin, in the family Solanaceae. The popular flower got its name from French, which took the word petun 'tobacco' from a Tupi-Guarani language. Most of the varieties seen in gardens are hybrids (Petunia x hybrida).