One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Glendive you can determine when it's a good idea to plant dahlias by using the USDA zone info.

Planting Calendar for Dahlias

Frost tolerance for dahlias:	Not tolerant of frost.
When to plant:	After the last frost has passed.

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

The earliest that you can plant dahlias 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 dahlias and expect a good harvest is probably August. You probably don't want to wait any later than that or else your dahlias may not have a chance to really do well. If you are starting your dahlias indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in Glendive. You should expect an average low temperature of -30°F in the coldest months of winter.

Always keep in mind 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 will vary from year to year. Since half of the time in Glendive you get surprised by a frost after May 15 be ready to cover your dahlias in the event of one of those late frosts.

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.