The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant iresene in Owatonna can be determined by using the USDA zone info.

Planting Calendar for Iresene

Frost tolerance for iresene:	Not tolerant of frost.
When to plant:	After the last frost.

Since iresene require warm weather you really should wait until after the last frost has passed before you can plant them.

The earliest that you can plant iresene in Owatonna 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 iresene and expect a good harvest is probably August. You probably don't want to wait any later than that or else your iresene may not have a chance to fully mature. If you are starting your iresene indoors then you might be able to get away with starting them a little bit 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 just an average the actual date of last frost will vary from year to year. Half of the time in Owatonna there is a last frost after May 15 so be sure to be ready to protect your iresene if you have one of those late frosts.

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.