One of the first steps you take when you are figuring out 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.

You should be able to determine when to plant strawflowers by using the USDA zone info for Thief River Falls.

Planting Calendar for Strawflowers

Frost tolerance for strawflowers:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Strawflowers can survive in mild cold which tells us that you can plant them slightly earlier in the year than more sensitive plants.

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

The last month that you can plant strawflowers and expect a good harvest is probably August. Any later than that and your strawflowers may not have a chance to grow to maturity. You can get started a little bit earlier by starting your strawflowers 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 can expect an average low temperature of -35°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Thief River Falls and it will vary from year to year. Half of the time in Thief River Falls it frosts late in the year after May 15 so always be ready to cover your strawflowers in the event of a late frost.

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.