Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of estimating when to plant calliopsis is to check out the USDA zone info for Bozeman.

Planting Calendar for Calliopsis

Frost tolerance for calliopsis:	Not tolerant of frost.
When to plant:	After the last frost.

Calliopsis are not cold tolerant which tells us that you really should wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant calliopsis in Bozeman is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant calliopsis and expect a good harvest is probably August. You probably don't want to wait any later than that or else your calliopsis may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your calliopsis indoors.

Last Frost Date

In Bozeman the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Bozeman and it can change quite a bit from year to year. Since half of the time in Bozeman last frost occurs after May 15 be ready to protect your calliopsis if you have a late frost.

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.