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

A common way of determining when it's possible to plant polygonums is to refer to the USDA zone info for Albert Lea.

Planting Calendar for Polygonums

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

You can not plant polygonums until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant polygonums in Albert Lea 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. Starting your polygonums indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Albert Lea. In the coldest months of winter you can expect an average low temperature of -25°F.

Remember that USDA zone info for Albert Lea is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Albert Lea you get surprised by a frost after May 15 so make sure that you are ready to protect your polygonums if you have one of those late frosts.

USDA Zone Info for Albert Lea

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 Albert Lea

You may be interested in your other planting guides for Albert Lea.