A winter benchmark
Each half-zone covers a 5°F band of average annual extreme minimum temperature.
Find your growing zone.
Search by ZIP code, postal code, city, or current location. We’ll show an official U.S. zone or a clearly labeled global estimate.
Look up my zone
Where are you planting?
Search a city or postal code to check the winter cold your perennial plants need to handle.
Your location is not stored.
Location data © OpenStreetMap contributors. Global estimates use NASA POWER data.
What your zone can tell you
A hardiness zone is a useful first screen for perennial cold tolerance. It does not measure sunlight, summer heat, soil, drainage, or water.
Official or estimated
U.S. ZIP results use the 2023 USDA map. Other locations receive a clearly labeled equivalent.
One part of plant fit
Sun, heat, soil, drainage, water, and local plant knowledge still shape success.
Know your zone. Then choose plants.
Read the zone guide for local caveats, or use the plant finder to add sunlight, project type, style, and care priorities.
Growing zone questions
What is a growing zone?
A growing zone, also called a plant hardiness zone, groups places by their average annual extreme minimum temperature. It is a useful first screen for perennial cold tolerance, not a guarantee that a plant will thrive.
Is my result an official USDA zone?
For a supported U.S. ZIP code, Gardenful uses the official 2023 USDA and PRISM ZIP code dataset. Outside that map, the tool labels the result as a USDA-equivalent estimate based on NASA global climate data.
Does the finder work outside the United States?
Yes. It calculates a USDA-equivalent estimate from the average coldest temperature in each year from 1991 to 2020. The result is useful for comparison, but it is not an official local government zone.
Why might my garden feel warmer or colder than the result?
Hardiness maps cannot capture every small microclimate. Elevation, slopes, frost pockets, walls, pavement, wind, and nearby water can shift the conditions in an individual garden.
Is a growing zone enough to choose plants?
No. After cold tolerance, check sunlight, summer heat, soil, drainage, moisture, mature size, and local guidance. Gardenful's plant finder adds several of those next filters.
Method sources: USDA Plant Hardiness Zone Map, PRISM 2023 ZIP data, and NASA POWER daily climate data. PRISM Group, Oregon State University data accessed July 25, 2026.