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.

By looking at the USDA zone info for Thief River Falls it's a good idea to determine when you can plant gayfeather.

Planting Calendar for Gayfeather

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

Since gayfeather do well in cold you can plant them quite a bit earlier in the year than more sensitive plants.

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

Last Frost Date

On average the last frost has passed is on May 15 in Thief River Falls. You should expect an average low temperature of -35°F in the coldest months of winter.

Since the USDA zone info for Thief River Falls is not always accurate the actual date of last frost changes from year to year. Half of the time in Thief River Falls last frost occurs after May 15 so make sure that you are ready to cover your gayfeather if you have 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.