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

The earliest that you can plant polygonums in Chisholm should be estimated by reviewing the USDA zone info.

Planting Calendar for Polygonums

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

It's probably a bad idea to plant polygonums until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant polygonums in Chisholm 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. Any later than that and 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

On average all chance of frost has passed is on May 15 in Chisholm. It might get as low as -35°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Chisholm may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Chisholm there is a last frost after May 15 so be sure to be ready to protect your polygonums if you have a surprise late frost.

USDA Zone Info for Chisholm

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-35°F
Highest Expected Low	-30°F

This means that on a really cold year, the coldest it will get is -35°F. On most years you should be prepared to experience lows near -30°F.

Plants to Grow in Chisholm

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