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When to Plant Hypericum in Thief River Falls, MN

Before planting it is a good idea to find your USDA Zone info to determine 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.

You will be able to estimate when it's the best time to plant hypericum by looking at the USDA zone info for Thief River Falls.


Planting Calendar for Hypericum

Frost tolerance for hypericum: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Hypericum do ok in moderate cold which means that you can get them planted just a bit earlier than other frost tender plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant hypericum
Possibly ok, but a risky time to plant hypericum
Probably not a good time to plant hypericum

The earliest that you can plant hypericum in Thief River Falls is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant hypericum and expect a good harvest is probably August. Any later than that and your hypericum may not have a chance to really do well. If you are starting your hypericum indoors then you might be able to get away with starting them a few weeks 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.

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 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 hypericum 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.