Coneflowers, penstemons, yarrows, maybe annual vinca, dahlias, small flowered zinnias?
Or you could go the California native plant route. Check out this native nursery:
http://www.laspilitas.com/ The Escondido nursery may be close enough to your daughter's place to warrant a visit. Scroll down to the bottom of the home page for a link on how-to for native plant gardens. (Yes, you will have to water the first year.)
Good luck!