One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant fennel in San Diego can be determined by using the USDA zone info.

Planting Calendar for Fennel

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

You can plant fennel quite a bit earlier in the year because they do well in cold.

The earliest that you can plant fennel in San Diego 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 really do well. Starting your fennel indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in San Diego. It might get as low as 35°F during the coldest months of winter.

Since the USDA zone info for San Diego is just an average the actual date of last frost changes from year to year. Half of the time in San Diego last frost occurs after January 31 so just be sure to be ready to protect your fennel if you have one of those late frosts.

USDA Zone Info for San Diego

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in San Diego

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