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

The first opportunity to plant sunflowers in Owatonna should be figured out by using the USDA zone info.

Planting Calendar for Sunflowers

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

Sunflowers do not do well in cold weather which means that it's important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant sunflowers 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 sunflowers and expect a good harvest is probably August. You probably don't want to wait any later than that or else your sunflowers may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your sunflowers indoors.

Last Frost Date

On average the last frost has passed is on May 15 in Owatonna. You can expect an average low temperature of -25°F in the coldest months of winter.

Always keep in mind that USDA zone info for Owatonna is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Owatonna there is a last frost after May 15 be ready to cover your sunflowers in the event of 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.