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.

A common way of determining when it's the best time to plant radicchio is to look at the USDA zone info for Knoxville.

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 little earlier in the year because they do well in moderate cold.

The earliest that you can plant radicchio in Knoxville 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. If you wait any later than that and your radicchio may not have a chance to really do well. If you are starting your radicchio indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Knoxville. It might get as low as 0°F during the coldest months of winter.

Keep in mind that USDA zone info for Knoxville is not always accurate and the actual date of last frost is different every year. Since half of the time in Knoxville there is a last frost after April 15 be ready to protect your radicchio if you have a surprise late frost.

USDA Zone Info for Knoxville

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Knoxville

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