The USDA divides the United States into seven planting regions, known as hardiness zones, which were most recently updated in 2023. The maps below show these planting regions.

The USDA divides the United States into seven planting regions, known as hardiness zones, which were most recently updated in 2023. The maps below show these planting regions.

Future planting zone shifts in U.S. cities Climate Central also used climate models to project how planting zones could shift by the middle of the century, assuming global pledged commitments to ...

With unabated climate change, about 90 percent of locations examined will likely shift to warmer planting zones by the middle of this century. The Upper Midwest is predicted to be affected most.

Lettuce is best suited for zones 4–10, with Rubens adding it works well when planting with carrots, radishes, and cucumbers. (See our USDA plant hardiness zone checker for more info on zones).