One of the first steps you take when you are figuring out 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.

The USDA zone info for Zone 5b can be looked at to figure out 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.

Liatris are very cold tolerant which means that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant liatris in Zone 5b 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. You probably don't want to wait any later than that or else your liatris may not have a chance to fully mature. If you are starting your liatris indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Zone 5b. You should expect an average low temperature of -15°F in the coldest months of winter.

It's important to remember that USDA zone info for Zone 5b may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Zone 5b there is a last frost after April 15 so always be ready to protect your liatris in the event of a surprise late frost.

USDA Zone Info for Zone 5b

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Zone 5b

You may be interested in your other planting guides for Zone 5b.