One of the best tools that you have as gardeners to help us figure out 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 best time to plant radicchio in San Luis Obispo should be determined 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.

Radicchio can survive in some cold which means that you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant radicchio in San Luis Obispo 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. If you wait 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 February 15 in San Luis Obispo. In the coldest months of winter you can expect an average low temperature of 25°F.

Since the USDA zone info for San Luis Obispo is an average the actual date of last frost can change quite a bit from year to year. Half of the time in San Luis Obispo you get surprised by a frost after February 15 so always be ready to cover your radicchio if you have one of those late frosts.

USDA Zone Info for San Luis Obispo

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 San Luis Obispo

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