One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's possible to figure out when you can plant tall phlox by looking at the USDA zone info for Joliet.

Planting Calendar for Tall Phlox

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

Since tall phlox are one of those plants that can tolerate a little bit of cold weather you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant tall phlox in Joliet 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. You probably don't want to wait any later than that or else 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 little bit earlier.

Last Frost Date

In Joliet the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Joliet is just an average the actual date of last frost is different every year. Since half of the time in Joliet it frosts late in the year after April 15 be ready to protect your tall phlox in the event of a surprise late frost.

USDA Zone Info for Joliet

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Joliet

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