One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant radicchio in Irvine should be estimated by referring to 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.

Since radicchio are moderately cold tolerant you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant radicchio in Irvine 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

The average date of last frost is January 31 in Irvine. You can expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Irvine may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Irvine last frost occurs after January 31 be ready to cover your radicchio in the event of a surprise late frost.

USDA Zone Info for Irvine

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 Irvine

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