One of the best tools that you have as gardeners to help us determine 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.

You can figure out when it's a good idea to plant foxglove in Knoxville by looking at the USDA zone info.

Planting Calendar for Foxglove

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

Since foxglove are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant foxglove 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 foxglove and expect a good harvest is probably September. Any later than that and your foxglove may not have a chance to really do well. Starting your foxglove indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Knoxville. In the coldest months of winter you should expect an average low temperature of -15°F.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Knoxville and it is different every year. Since half of the time in Knoxville last frost occurs after April 15 be ready to protect your foxglove if you have a surprise late frost.

USDA Zone Info for Knoxville

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Knoxville

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