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

In Bonne Terre you can estimate when it's the best time to plant liatris by reviewing 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.

You can plant liatris quite a bit earlier in the year because they do well in cold.

The earliest that you can plant liatris in Bonne Terre 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 grow to maturity. You can get started a few weeks earlier by starting your liatris indoors.

Last Frost Date

The average date of last frost is April 15 in Bonne Terre. You can expect an average low temperature of -10°F in the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Bonne Terre and it changes from year to year. Since half of the time in Bonne Terre there is a last frost after April 15 be ready to cover your liatris in the event of a late frost.

USDA Zone Info for Bonne Terre

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 Bonne Terre

You may be interested in your other planting guides for Bonne Terre.