Browse All USDA Hardiness Zones
Find your zone and discover the best grasses, calendars, and care tips.
Zone 3B
Cold continental
-35° to -30°F

Zone 4A
Cold continental
-30° to -25°F

Zone 4B
Cold continental
-25° to -20°F

Zone 5A
Cool-season classic
-20° to -15°F

Zone 5B
Cool-season classic
-15° to -10°F

Zone 6A
Cool-season classic
-10° to -5°F

Zone 6B
Cool-season classic
-5° to 0°F

Zone 7A
Transition zone
0° to 5°F

Zone 7B
Transition zone
5° to 10°F

Zone 8A
Warm-season
10° to 15°F

Zone 8B
Warm-season
15° to 20°F

Zone 9A
Warm-season
20° to 25°F

Zone 9B
Warm-season
25° to 30°F

Zone 10A
Subtropical
30° to 35°F

Zone 10B
Subtropical
35° to 40°F

Zone 11A
Tropical
40° to 45°F

Zone 11B
Tropical
45° to 50°F

How USDA Hardiness Zones Work
What the numbers mean
USDA Hardiness Zones are based on the average annual extreme minimum temperature. Each zone represents a 10°F range, subdivided into “a” and “b” halves (5°F each). Zone 6a means winter lows average -10° to -5°F.
Why it matters for your lawn
Grass species have temperature limits. Planting Kentucky Bluegrass in Zone 10a will fail just as surely as Bermudagrass in Zone 4b. Your zone determines which grasses survive winter, when to seed, and how to time fertilization.
How we calculate your zone
We use PRISM climate data aggregated at the county level, matched to the USDA Plant Hardiness Zone Map. Enter your zip code and we map it to your county’s assigned zone — no guesswork, no averages across states.