The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant polygonums in Cortland should be determined by checking out 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.

It's a bad idea to plant polygonums until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant polygonums in Cortland 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 really do well. Starting your polygonums indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Cortland the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Cortland is just an average the actual date of last frost is different every year. Since half of the time in Cortland last frost occurs after April 15 be ready to cover your polygonums if you have a surprise late frost.

USDA Zone Info for Cortland

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Cortland

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