The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to determine when it's a good idea to plant fennel by using the USDA zone info for San Ramon.

Planting Calendar for Fennel

Frost tolerance for fennel:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Fennel do well in cold which means that you can plant them much earlier than other plants that might not handle the cold.

The earliest that you can plant fennel in San Ramon is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant fennel and expect a good harvest is probably October. Any later than that and your fennel may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your fennel indoors.

Last Frost Date

In San Ramon the average date of last frost happens on February 15. You should expect an average low temperature of 25°F in the coldest months of winter.

Remember that USDA zone info for San Ramon may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in San Ramon you get a frost after February 15 be ready to protect your fennel if you have a surprise late frost.

USDA Zone Info for San Ramon

Here is the info for USDA Zone 9b.

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.

Plants to Grow in San Ramon

You may be interested in your other planting guides for San Ramon.