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.

A way of determining when you can plant polygonums is to examine the USDA zone info for De Witt.

Planting Calendar for Polygonums

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

Since polygonums require warm weather it is necessary to wait until after the last frost before you can plant them.

The earliest that you can plant polygonums in De Witt is April. However, you really should wait until May 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 fully mature. You can get started a little bit earlier by starting your polygonums indoors.

Last Frost Date

The average date of last frost is April 15 in De Witt. You can expect an average low temperature of -20°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for De Witt and it will vary from year to year. Half of the time in De Witt you get a frost after April 15 so be sure to be ready to protect your polygonums in the event of one of those late frosts.

USDA Zone Info for De Witt

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in De Witt

You may be interested in your other planting guides for De Witt.