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

By referring to the USDA zone info for Louisville it's a good idea to figure out when it's possible to plant bee balm.

Planting Calendar for Bee Balm

Frost tolerance for bee balm:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since bee balm do ok in moderate cold you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant bee balm in Louisville is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant bee balm and expect a good harvest is probably August. You probably don't want to wait any later than that or else your bee balm may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your bee balm indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Louisville. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Louisville is an average the actual date of last frost changes from year to year. Half of the time in Louisville you get surprised by a frost after April 15 so just be sure to be ready to cover your bee balm in the event of a late frost.

USDA Zone Info for Louisville

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Louisville

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