One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to figure out when it's a good idea to plant liatris by referring to the USDA zone info for Bozeman.

Planting Calendar for Liatris

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

Liatris do well in cold which tells us that you can plant them much earlier than other plants that might not handle the cold.

The earliest that you can plant liatris in Bozeman 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 Bozeman. In the coldest months of winter you can expect an average low temperature of -25°F.

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 Bozeman and it changes from year to year. Since half of the time in Bozeman it frosts late in the year after May 15 be ready to protect your liatris if you have one of those late frosts.

USDA Zone Info for Bozeman

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 Bozeman

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