One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of determining when you can plant radicchio is to examine the USDA zone info for South San Francisco.

Planting Calendar for Radicchio

Frost tolerance for radicchio:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Radicchio can survive in mild cold which tells us that you can plant them a little bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant radicchio in South San Francisco 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 radicchio and expect a good harvest is probably October. Any later than that and your radicchio may not have a chance to fully mature. Starting your radicchio indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

It's important to remember that USDA zone info for South San Francisco may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in South San Francisco last frost occurs after January 31 so always be ready to cover your radicchio in the event of a surprise late frost.

USDA Zone Info for South San Francisco

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 South San Francisco

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