Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Storm Lake you can estimate when it's possible to plant polygonums by looking at the USDA zone info.

Planting Calendar for Polygonums

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

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

The earliest that you can plant polygonums in Storm Lake 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 really do well. You can get started a little bit earlier by starting your polygonums indoors.

Last Frost Date

On average the last frost is on April 15 in Storm Lake. In the coldest months of winter you should expect an average low temperature of -20°F.

Just be sure to remember that USDA zone info for Storm Lake may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Storm Lake you get a frost after April 15 be ready to cover your polygonums in the event of a late frost.

USDA Zone Info for Storm Lake

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 Storm Lake

You may be interested in your other planting guides for Storm Lake.