One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Louisville should be used to figure out when it's a good idea to plant tall phlox.

Planting Calendar for Tall Phlox

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

You can plant tall phlox a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant tall 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 tall phlox and expect a good harvest is probably September. If you wait any later than that and your tall phlox may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your tall phlox indoors.

Last Frost Date

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

It's important to remember that USDA zone info for Louisville is just an average and the actual date of last frost is different every year. Since half of the time in Louisville there is a last frost after April 15 be ready to protect your tall phlox if you have a surprise late frost.

USDA Zone Info for Louisville

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 Louisville

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