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.

One way of estimating when to plant polygonums is to examine the USDA zone info for Petersburg.

Planting Calendar for Polygonums

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

Since polygonums do not do well in cold weather you need to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant polygonums in Petersburg 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 fully mature. You can get started a couple of weeks earlier by starting your polygonums indoors.

Last Frost Date

The average date of last frost is April 15 in Petersburg. In the coldest months of winter you can expect an average low temperature of 5°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Petersburg and it changes from year to year. Half of the time in Petersburg you get a frost after April 15 so just be sure to be ready to protect your polygonums in the event of a late frost.

USDA Zone Info for Petersburg

Here is the info for USDA Zone 7b.

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

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

Plants to Grow in Petersburg

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