Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to determine when you can plant phlox by checking out the USDA zone info for Mattoon.

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 Mattoon 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. Any later than that and your phlox may not have a chance to fully mature. Starting your phlox indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Mattoon. You should expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Mattoon may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Mattoon there is a last frost after April 15 so make sure that you are ready to protect your phlox in the event of a late frost.

USDA Zone Info for Mattoon

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 Mattoon

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