One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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 Park Forest should be reffered to in order to estimate when it's the best time to plant liatris.

Planting Calendar for Liatris

Frost tolerance for liatris:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since liatris do well in cold you can plant them a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant liatris in Park Forest 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 liatris and expect a good harvest is probably September. If you wait any later than that and your liatris may not have a chance to fully mature. If you are starting your liatris indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Park Forest is an average the actual date of last frost changes from year to year. Half of the time in Park Forest you get a frost after April 15 so always be ready to cover your liatris if you have a surprise late frost.

USDA Zone Info for Park Forest

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 Park Forest

You may be interested in your other planting guides for Park Forest.