Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Knoxville should be reviewed to figure out when it's possible to plant sorrel.

Planting Calendar for Sorrel

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

Sorrel do ok in a little bit of cold which tells us that you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant sorrel 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 sorrel and expect a good harvest is probably September. Any later than that and your sorrel may not have a chance to grow to maturity. If you are starting your sorrel indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Knoxville. In the coldest months of winter you should expect an average low temperature of 0°F.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Knoxville and it will vary from year to year. Since half of the time in Knoxville you get surprised by a frost after April 15 be ready to protect your sorrel if you have a 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.