Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of figuring out when it's a good idea to plant fennel is to look at the USDA zone info for San Bruno.

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 a lot earlier in the year because they are very cold tolerant.

The earliest that you can plant fennel in San Bruno 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. If you wait any later than that and your fennel may not have a chance to really do well. If you are starting your fennel indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is January 31 in San Bruno. You can expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for San Bruno is just an average the actual date of last frost is different every year. Half of the time in San Bruno last frost occurs after January 31 so make sure that you are ready to cover your fennel in the event of a late frost.

USDA Zone Info for San Bruno

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in San Bruno

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