One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By referring to the USDA zone info for Smithfield it's a good idea to estimate when it's a good idea to plant polygonums.

Planting Calendar for Polygonums

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

Since polygonums are not cold tolerant it's necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant polygonums in Smithfield 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 really do well. You can get started a few weeks earlier by starting your polygonums indoors.

Last Frost Date

In Smithfield the average date of last frost happens on March 15. It might get as low as 10°F during the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Smithfield and it changes from year to year. Half of the time in Smithfield you get surprised by a frost after March 15 so always be ready to cover your polygonums in the event of a late frost.

USDA Zone Info for Smithfield

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Smithfield

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