One of the best tools that you have as gardeners to help us figure out 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 will be able to determine when you can plant polygonums by using the USDA zone info for Morris.

Planting Calendar for Polygonums

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

It's probably not a good idea to plant polygonums until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant polygonums in Morris 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. You can get started a couple of weeks earlier by starting your polygonums indoors.

Last Frost Date

The average date of last frost is May 15 in Morris. It might get as low as -30°F during the coldest months of winter.

Since the USDA zone info for Morris is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Morris there is a last frost after May 15 so always be ready to protect your polygonums if you have a surprise late frost.

USDA Zone Info for Morris

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 Morris

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