Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Yankton should be reviewed to estimate when you can plant polygonums.

Planting Calendar for Polygonums

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

Polygonums are not cold tolerant which means that you must wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant polygonums in Yankton 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. 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 couple of weeks earlier.

Last Frost Date

In Yankton the average date of last frost happens on April 15. You can expect an average low temperature of -20°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Yankton is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Yankton last frost occurs after April 15 be ready to protect your polygonums if you have a surprise late frost.

USDA Zone Info for Yankton

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Yankton

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