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

In Thief River Falls you can estimate when it's the best time to plant evolvulus by reviewing the USDA zone info.

Planting Calendar for Evolvulus

Frost tolerance for evolvulus:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's not a good idea to plant evolvulus until after the last frost has passed because they require warm weather.

The earliest that you can plant evolvulus in Thief River Falls 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 evolvulus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your evolvulus may not have a chance to fully mature. If you are starting your evolvulus indoors then you might be able to get away with starting them a couple of weeks earlier.

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 USDA zone info for Thief River Falls is not always accurate and the actual date of last frost is different every year. Since half of the time in Thief River Falls last frost occurs after May 15 be ready to cover your evolvulus 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.