Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of getting a good idea when it's possible to plant tall phlox is to look at the USDA zone info for Clarks Summit.

Planting Calendar for Tall Phlox

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

Tall Phlox do ok in some cold which means that you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant tall phlox in Clarks Summit 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. Any later than that and your tall phlox may not have a chance to really do well. Starting your tall phlox indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Clarks Summit the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Clarks Summit is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Clarks Summit it frosts late in the year after April 15 so always be ready to cover your tall phlox in the event of a late frost.

USDA Zone Info for Clarks Summit

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 Clarks Summit

You may be interested in your other planting guides for Clarks Summit.