Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to estimate when it's a good idea to plant flower-of-an-hour by reviewing the USDA zone info for Owatonna.

Planting Calendar for Flower-of-an-Hour

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

Flower-of-an-Hour are barely cold tolerant which tells us that you can plant them slightly earlier than other frost tender plants.

The earliest that you can plant flower-of-an-hour 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 flower-of-an-hour and expect a good harvest is probably August. Any later than that and your flower-of-an-hour may not have a chance to fully mature. Starting your flower-of-an-hour 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. In the coldest months of winter you should expect an average low temperature of -25°F.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Owatonna and it can change quite a bit from year to year. Since half of the time in Owatonna you get surprised by a frost after May 15 be ready to protect your flower-of-an-hour in the event of a 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.