One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By referring to the USDA zone info for Owatonna it's a good idea to determine when to plant hypericum.

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 tend to make it in mild cold which tells us that you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant hypericum in Owatonna 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. You probably don't want to wait any later than that or else your hypericum may not have a chance to fully mature. Starting your hypericum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Owatonna the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Owatonna is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Owatonna it frosts late in the year after May 15 be ready to cover your hypericum in the event of a surprise late frost.

USDA Zone Info for Owatonna

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Owatonna

You may be interested in your other planting guides for Owatonna.