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.

You should be able to determine when you can plant chrysanthemum by looking at the USDA zone info for Thief River Falls.

Planting Calendar for Chrysanthemum

Frost tolerance for chrysanthemum:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Chrysanthemum do not do well in cold weather which tells us that you really should wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant chrysanthemum 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 chrysanthemum and expect a good harvest is probably August. Any later than that and your chrysanthemum may not have a chance to grow to maturity. You can get started a little bit earlier by starting your chrysanthemum indoors.

Last Frost Date

On average the last frost has passed 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 USDA zone info for Thief River Falls is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Thief River Falls last frost occurs after May 15 so be sure to be ready to cover your chrysanthemum if you have a surprise 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.