One of the best tools that you have as gardeners to help us estimate 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 can determine when it's the best time to plant polygonums in East Grand Forks by referring to the USDA zone info.

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 really should wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant polygonums in East Grand Forks is May. However, you really should wait until June 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. If you wait any later than that and your polygonums may not have a chance to fully mature. Starting your polygonums indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on May 15 in East Grand Forks. It might get as low as -30°F during the coldest months of winter.

Keep in mind that USDA zone info for East Grand Forks is just an average and the actual date of last frost changes from year to year. Since half of the time in East Grand Forks you get surprised by a frost after May 15 be ready to cover your polygonums in the event of a late frost.

USDA Zone Info for East Grand Forks

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in East Grand Forks

You may be interested in your other planting guides for East Grand Forks.