Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Thief River Falls can be read to figure out when you can plant creeping phlox.

Planting Calendar for Creeping Phlox

Frost tolerance for creeping phlox:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since creeping phlox are one of those plants that can tolerate quite a bit of cold weather you can plant them quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant creeping phlox in Thief River Falls is March. However, you really should wait until April if you don't want to take any chances.

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

Last Frost Date

In Thief River Falls the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -35°F.

Since the USDA zone info for Thief River Falls is just an average the actual date of last frost changes from year to year. Half of the time in Thief River Falls there is a last frost after May 15 so just be sure to be ready to cover your creeping phlox in the event of one of those late frosts.

USDA Zone Info for Thief River Falls

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-35°F
Highest Expected Low	-30°F

This means that on a really cold year, the coldest it will get is -35°F. On most years you should be prepared to experience lows near -30°F.

Plants to Grow in Thief River Falls

You may be interested in your other planting guides for Thief River Falls.