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

You should be able to determine when to plant polygonums by using the USDA zone info for Westerville.

Planting Calendar for Polygonums

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

Since polygonums require warm weather you really should wait until after the last frost has passed before you can plant them.

The earliest that you can plant polygonums in Westerville 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. Any later than that and your polygonums may not have a chance to grow to maturity. If you are starting your polygonums indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Westerville the average date of last frost happens on April 15. You can expect an average low temperature of -10°F in the coldest months of winter.

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

USDA Zone Info for Westerville

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Westerville

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