One of the best tools that you have as gardeners to help us estimate 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 first chance to plant calliopsis in Glendive should be figured out by looking at the USDA zone info.

Planting Calendar for Calliopsis

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

Since calliopsis do not do well in cold weather you need to wait until after the last frost before you can plant them.

The earliest that you can plant calliopsis in Glendive 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 little bit earlier by starting your calliopsis indoors.

Last Frost Date

In Glendive the average date of last frost happens on May 15. It might get as low as -30°F during the coldest months of winter.

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 Glendive and it is different every year. Half of the time in Glendive it frosts late in the year after May 15 so be sure to be ready to cover your calliopsis in the event of a surprise late frost.

USDA Zone Info for Glendive

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Glendive

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