Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By checking out the USDA zone info for Thief River Falls you should be able to estimate when you can plant violas.

Planting Calendar for Violas

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

Violas can survive in cold weather which means that you can plant them much earlier in the year than more sensitive plants.

The earliest that you can plant violas 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 violas and expect a good harvest is probably August. You probably don't want to wait any later than that or else your violas may not have a chance to fully mature. Starting your violas indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Thief River Falls the average date of last frost happens on May 15. You can expect an average low temperature of -35°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Thief River Falls and it is different every year. Since half of the time in Thief River Falls it frosts late in the year after May 15 be ready to protect your violas 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.