Here is some general info for USDA zone 9b to help you get started.
|Average Date of Last Frost (spring)||February 15|
|Average Date of First Frost (fall)||December 15|
|Lowest Expected Low||25°F|
|Highest Expected Low||30°F|
This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.
Below is a list of planting guides for Zone 9b.