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.

A common way of estimating when to plant liatris is to check out the USDA zone info for Viroqua.

Planting Calendar for Liatris

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

Liatris are one of those plants that can tolerate quite a bit of cold weather which tells us that you can start planting them much earlier than other plants that might not handle the cold.

The earliest that you can plant liatris in Viroqua is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant liatris and expect a good harvest is probably August. Any later than that and your liatris may not have a chance to fully mature. You can get started a few weeks earlier by starting your liatris indoors.

Last Frost Date

The average date of last frost is May 15 in Viroqua. It might get as low as -25°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Viroqua and it can change quite a bit from year to year. Since half of the time in Viroqua there is a last frost after May 15 be ready to protect your liatris in the event of a late frost.

USDA Zone Info for Viroqua

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Viroqua

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