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.

You will be able to determine when it's a good idea to plant mustard by reviewing the USDA zone info for Thief River Falls.

Planting Calendar for Mustard

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

Mustard do not do well in cold weather which tells us that you need to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant mustard 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 mustard and expect a good harvest is probably August. Any later than that and your mustard may not have a chance to grow to maturity. Starting your mustard indoors is a great way to get them started a few 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.

Since the USDA zone info for Thief River Falls is not always accurate the actual date of last frost changes from year to year. Since half of the time in Thief River Falls last frost occurs after May 15 be ready to cover your mustard if you have 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.