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

By referring to the USDA zone info for Mankato you will be able to determine when to plant sweet potatos.

Planting Calendar for Sweet Potatos

Frost tolerance for sweet potatos:	Not tolerant of frost.
When to plant:	After the last frost has passed.

It's probably a bad idea to plant sweet potatos until after the last frost because they do not do well in cold weather.

The earliest that you can plant sweet potatos in Mankato 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 sweet potatos and expect a good harvest is probably August. You probably don't want to wait any later than that or else your sweet potatos may not have a chance to really do well. Starting your sweet potatos indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Mankato. In the coldest months of winter you can expect an average low temperature of -25°F.

Keep in mind 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 Mankato and it can change quite a bit from year to year. Half of the time in Mankato you get a frost after May 15 so make sure that you are ready to protect your sweet potatos in the event of a late frost.

USDA Zone Info for Mankato

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 Mankato

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