Plant Hardiness Zones By Zip Code 2025. Enter your zip code in the search box to find your location in the plant hardiness zone map. On a recent visit to a plant nursery outside washington, d.c., nearly every plant tag had a usda hardiness zone, but only one, out of the several dozen checked, had the ahs heat zone listed.

Each growing zone is 10°f warmer (or colder) in an average winter than the adjacent zone. Gardeners use the usda plant hardiness zone map to check which plants can grow where.