One of the best tools that you have as gardeners to help us estimate 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.

The earliest that you can plant radicchio in Cupertino should be estimated by looking at the USDA zone info.

Planting Calendar for Radicchio

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

You can plant radicchio a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant radicchio in Cupertino 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 little bit earlier by starting your radicchio indoors.

Last Frost Date

The average date of last frost is February 15 in Cupertino. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Cupertino is not always accurate the actual date of last frost changes from year to year. Half of the time in Cupertino there is a last frost after February 15 so always be ready to cover your radicchio if you have a late frost.

USDA Zone Info for Cupertino

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 Cupertino

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