One of the best tools that you have as gardeners to help us estimate 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.

In Vincennes you can figure out when to plant liatris by using the USDA zone info.

Planting Calendar for Liatris

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

Liatris can survive in cold weather which tells us that you can plant them quite a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant liatris in Vincennes 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 really do well. If you are starting your liatris indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Vincennes. You can expect an average low temperature of -10°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Vincennes is an average and the actual date of last frost changes from year to year. Half of the time in Vincennes you get a frost after April 15 so be sure to be ready to cover your liatris in the event of a late frost.

USDA Zone Info for Vincennes

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 Vincennes

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