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 can figure out when it's the best time to plant nasturtium in Thief River Falls by using the USDA zone info.

Planting Calendar for Nasturtium

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

Nasturtium 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 nasturtium 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 nasturtium and expect a good harvest is probably August. You probably don't want to wait any later than that or else your nasturtium may not have a chance to really do well. If you are starting your nasturtium indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Thief River Falls may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Thief River Falls you get a frost after May 15 be ready to cover your nasturtium 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.