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

In Herrin you can determine when it's possible to plant radicchio 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.

Radicchio are moderately cold tolerant which means that you can plant them a little bit earlier than other plants that might not handle the cold.

The earliest that you can plant radicchio in Herrin is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant radicchio and expect a good harvest is probably September. 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 little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Herrin. You should expect an average low temperature of -5°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Herrin is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Herrin last frost occurs after April 15 be ready to cover your radicchio if you have one of those late frosts.

USDA Zone Info for Herrin

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Herrin

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