Hi Maureen,
Carmona is an older name for a genus now known as Ehretia. The common name of the plant is "Fukien Tea."
You can find some general care information on the
BCI species page here This is one of the few species that you would probably want to overwinter indoors unless you are in a very mild climate without frost.
Please also take a look on this board in the section labeled bonsai FAQ for the information about watering.