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.

The earliest that you can plant polygonums in Mankato should be estimated by referring to the USDA zone info.

Planting Calendar for Polygonums

Frost tolerance for polygonums:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's probably not a good idea to plant polygonums until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant polygonums 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 polygonums and expect a good harvest is probably August. Any later than that and your polygonums may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your polygonums indoors.

Last Frost Date

In Mankato the average date of last frost happens on May 15. You can expect an average low temperature of -25°F in the coldest months of winter.

Remember 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 will vary from year to year. Since half of the time in Mankato you get a frost after May 15 be ready to protect your polygonums in the event of a surprise 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.