How to Find Your USDA Plant Hardiness Zone

North America is divided into 10 cold-hardiness zones by the U.S. Department of Agriculture. (It’s also divided into 12 heat zones, but those are not usually a concern in northern climates.)

Hardiness zones are based on the lowest low temperature an area is likely to experience. If you live in Rochester, MN, for example, your lowest low (according to the USDA hardiness map) is going to be between -20 and -25 degrees F. If you live in Cook, MN, the lowest low will likely be between -35 and -40 degrees F.

upper midwest hardiness zones

Knowing your plant hardiness zone matters because plants are rated for hardiness (whether they will survive winter) based on these zones.

The map above shows the north central region of the United States, which ranges from zone 7 in far southern Missouri to zone 3 in northern Minnesota and North Dakota.

Mary Lahr Schier is a longtime Minnesota garden writer and speaker. Follow her on Instagram at @mynortherngarden_mary.

LIKE THIS BLOG?

Learn more in Northern Gardener® magazine…

Four seasonal issues full of growing tips and featured gardens—written and edited by local northern gardening pros just for you.

2 Comments

  1. Paul Sundberg says:

    I would love to see a close-up of this image, but it is illegible and almost useless at the size here. Could it maybe be clickable with a link to a fuller-sized image that site visitors could read?

    1. Mary Lahr Schier says:

      Working on fixing this now.

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to Blog