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.

By looking at the USDA zone info for Louisville it's possible to estimate when to plant phlox.

Planting Calendar for Phlox

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

You can plant phlox a little bit earlier in the year because they do well in moderate cold.

The earliest that you can plant phlox in Louisville 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 phlox and expect a good harvest is probably September. You probably don't want to wait any later than that or else your phlox may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your phlox indoors.

Last Frost Date

The average date of last frost is March 15 in Louisville. You should expect an average low temperature of 10°F in the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Louisville and it is different every year. Half of the time in Louisville last frost occurs after March 15 so be sure to be ready to protect your phlox if you have one of those late frosts.

USDA Zone Info for Louisville

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Louisville

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