There's a new Plant Hardiness Zone map from the USDA. About half of U.S. gardeners are now in a new zone. The 2023 map is more accurate than the previous version and more precise The USDA Plant Hardiness Zone Map is the standard by which gardeners and growers can determine which perennial plants are most likely to thrive at a location. The map is based on the average annual extreme minimum winter temperature, displayed as 10-degree F zones and 5-degree F half zones here: 2023 USDA Plant Hardiness Zone Map | USDA Plant Hardiness Zone Map