Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for San Diego you should be able to estimate when it's a good idea to plant radicchio.

Planting Calendar for Radicchio

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

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

The earliest that you can plant radicchio 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 radicchio and expect a good harvest is probably October. You probably don't want to wait any later than that or else your radicchio may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your radicchio indoors.

Last Frost Date

In San Diego the average date of last frost happens on February 15. It might get as low as 20°F during the coldest months of winter.

Always keep in mind that USDA zone info for San Diego is an average and the actual date of last frost will vary from year to year. Half of the time in San Diego there is a last frost after February 15 so be sure to be ready to cover your radicchio in the event of a surprise late frost.

USDA Zone Info for San Diego

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in San Diego

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