The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Atherton can be read to figure out when it's a good idea to plant fennel.

Planting Calendar for Fennel

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

Since fennel are one of those plants that can tolerate quite a bit of cold weather you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant fennel in Atherton 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. You probably don't want to wait any later than that or else 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 few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Atherton. It might get as low as 25°F during the coldest months of winter.

It's important to remember that USDA zone info for Atherton is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Atherton there is a last frost after February 15 be ready to protect your fennel if you have one of those late frosts.

USDA Zone Info for Atherton

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 Atherton

You may be interested in your other planting guides for Atherton.