The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant columbine in Knoxville can be figured out by referring to the USDA zone info.

Planting Calendar for Columbine

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

Columbine do well in moderate cold which means that you can plant them a little earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant columbine 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 columbine and expect a good harvest is probably September. You probably don't want to wait any later than that or else your columbine may not have a chance to really do well. Starting your columbine indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Knoxville the average date of last frost happens on April 15. You should expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Knoxville is an average 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 cover your columbine in the event of one of those late frosts.

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.