The USDA Zone info is a great tool for gardeners to help us estimate your gardening 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 Santa Rosa you will be able to estimate when 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.

Radicchio do well in some cold which tells us that you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant radicchio in Santa Rosa 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 fully mature. Starting your radicchio indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Santa Rosa the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 25°F.

Since the USDA zone info for Santa Rosa is an average the actual date of last frost is different every year. Half of the time in Santa Rosa you get a frost after February 15 so just be sure to be ready to protect your radicchio in the event of one of those late frosts.

USDA Zone Info for Santa Rosa

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 Santa Rosa

You may be interested in your other planting guides for Santa Rosa.