One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant polygonums in Zimmerman should be figured out by checking out the USDA zone info.

Planting Calendar for Polygonums

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

Polygonums require warm weather which means that you really should wait until it warms up after all chance of frost has passed before you can plant them.

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

Last Frost Date

In Zimmerman the average date of last frost happens on May 15. You should expect an average low temperature of -30°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Zimmerman is not always accurate and the actual date of last frost is different every year. Since half of the time in Zimmerman there is a last frost after May 15 be ready to cover your polygonums if you have one of those late frosts.

USDA Zone Info for Zimmerman

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Zimmerman

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