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 River Falls should be used to determine when it's a good idea 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.

You can plant liatris quite a bit earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant liatris in River Falls 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. You probably don't want to wait any later than that or else your liatris may not have a chance to fully mature. Starting your liatris indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in River Falls. You can expect an average low temperature of -25°F in the coldest months of winter.

Just be sure to remember that USDA zone info for River Falls is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in River Falls it frosts late in the year after May 15 be ready to cover your liatris if you have a late frost.

USDA Zone Info for River Falls

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 River Falls

You may be interested in your other planting guides for River Falls.