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.

It's a good idea to determine when to plant polygonums by referring to the USDA zone info for Urbana.

Planting Calendar for Polygonums

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

You really shouldn't plant polygonums until after the last frost has passed because they require warm weather.

The earliest that you can plant polygonums in Urbana 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. Any later than that and your polygonums may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your polygonums indoors.

Last Frost Date

The average date of last frost is April 15 in Urbana. You can expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Urbana may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Urbana you get a frost after April 15 so always be ready to protect your polygonums in the event of a surprise late frost.

USDA Zone Info for Urbana

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Urbana

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