One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Highland Park you will be able to determine when it's the best time to plant polygonums.

Planting Calendar for Polygonums

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

Polygonums do not do well in cold weather which tells us that you have to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant polygonums in Highland Park 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. You probably don't want to wait any later than that or else your polygonums may not have a chance to grow to maturity. Starting your polygonums indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Highland Park. In the coldest months of winter you can expect an average low temperature of 0°F.

Keep in mind that USDA zone info for Highland Park is just an average and the actual date of last frost changes from year to year. Half of the time in Highland Park you get a frost after April 15 so be sure to be ready to protect your polygonums in the event of one of those late frosts.

USDA Zone Info for Highland Park

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Highland Park

You may be interested in your other planting guides for Highland Park.