Us Hardiness Zones 2025. Posted on aug 17, 2025 1:15 pm edt. — september is a great time to plant perennial phlox, even in cold climates.
According to the new map released in november 2023, about half of the united states has shifted to a new hardiness zone. — usda’s plant hardiness zone map is the standard by which gardeners and growers can determine which plants are most likely to thrive at a location.