The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to estimate when it's a good idea to plant polygonums by looking at the USDA zone info for Glendive.

Planting Calendar for Polygonums

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

Since polygonums are not cold tolerant it's important to wait until after the last frost has passed before you can plant them.

The earliest that you can plant polygonums 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 polygonums and expect a good harvest is probably August. Any later than that and your polygonums may not have a chance to really do well. Starting your polygonums indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Glendive the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -30°F.

Since the USDA zone info for Glendive may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Glendive it frosts late in the year after May 15 so make sure that you are prepared to cover your polygonums in the event of a 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.