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.

In Joliet you can estimate when it's a good idea to plant phlox by checking out the USDA zone info.

Planting Calendar for Phlox

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

Phlox are one of those plants that can tolerate a little bit of cold weather which tells us that you can get them planted earlier than more sensitive plants.

The earliest that you can plant 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 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. If you are starting your phlox indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Joliet is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Joliet you get a frost after April 15 so always be ready to protect your phlox if you have a 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.