One of the best tools that you have as gardeners to help us figure out 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.

You should be able to figure out when it's a good idea to plant polygonums by looking at the USDA zone info for Sweetwater.

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 are not cold tolerant it is important to wait until after the last frost has passed before you can plant them.

The earliest that you can plant polygonums in Sweetwater 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. If you are starting your polygonums indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Sweetwater. You should expect an average low temperature of 5°F in the coldest months of winter.

Keep in mind that USDA zone info for Sweetwater is an average and the actual date of last frost is different every year. Half of the time in Sweetwater there is a last frost after April 15 so always be ready to cover your polygonums if you have a late frost.

USDA Zone Info for Sweetwater

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 Sweetwater

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