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

The first chance to plant fennel in Rio Vista can be figured out by looking at 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.

Fennel do ok in quite a bit of cold which tells us that you can plant them a lot earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant fennel in Rio Vista 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. You can get started a few weeks earlier by starting your fennel indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Rio Vista. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Rio Vista is just an average the actual date of last frost changes from year to year. Half of the time in Rio Vista last frost occurs after February 15 so always be ready to protect your fennel in the event of a late frost.

USDA Zone Info for Rio Vista

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 Rio Vista

You may be interested in your other planting guides for Rio Vista.