One of the best tools that you have as gardeners to help us determine 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.

The USDA zone info for Thief River Falls can be looked at to figure out when it's possible to plant monkey flower.

Planting Calendar for Monkey Flower

Frost tolerance for monkey flower:	Not tolerant of frost.
When to plant:	After the last frost.

It's a bad idea to plant monkey flower until after all chance of frost has passed because they do not do well in cold weather.

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

Last Frost Date

On average the last frost is on May 15 in Thief River Falls. It might get as low as -35°F during the coldest months of winter.

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. Since half of the time in Thief River Falls you get a frost after May 15 be ready to protect your monkey flower 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.