What Planting Zones Are in California?
California spans USDA hardiness zones 5b to 11a, where the average coldest winter night ranges from −15 °F to 45 °F (−26.1 °C to 7.2 °C). Zone 9b covers the most ZIP codes, 34%, and zones 9b to 10b together cover 79% of the state.
- Zone 5b<1% · 1 ZIP
- Zone 6a<1% · 7 ZIPs
- Zone 6b1% · 38 ZIPs
- Zone 7a2% · 41 ZIPs
- Zone 7b<1% · 24 ZIPs
- Zone 8a1% · 38 ZIPs
- Zone 8b4% · 112 ZIPs
- Zone 9a9% · 236 ZIPs
- Zone 9b34% · 879 ZIPs
- Zone 10a24% · 623 ZIPs
- Zone 10b21% · 527 ZIPs
- Zone 11a1% · 28 ZIPs
Bars show each zone's share of the 2,554 California ZIP codes in the official 2023 USDA ZIP code table; select a zone for its temperatures and hardy plants.
What Hardiness Zone Are California Cities In?
Los Angeles is in zone 10b, San Diego is in zone 10b, San Jose is in zone 9b and San Francisco is in zone 10a. The table lists the zone, winter low and average frost dates for 19 California cities, using the ZIP code nearest each city center.
| City | ZIP | Zone | Winter low | Last frost | First frost |
|---|---|---|---|---|---|
| Los Angeles | 90034 | 10b | 35 °F to 40 °F | Frost-free | Frost-free |
| San Diego | 92123 | 10b | 35 °F to 40 °F | Frost-free | Frost-free |
| San Jose | 95121 | 9b | 25 °F to 30 °F | Jan 2 | Dec 25 |
| San Francisco | 94924 | 10a | 30 °F to 35 °F | Jan 16 | Dec 18 |
| Fresno | 93704 | 9b | 25 °F to 30 °F | Jan 14 | Dec 14 |
| Sacramento | 95816 | 9b | 25 °F to 30 °F | Jan 12 | Dec 16 |
| Long Beach | 90804 | 10b | 35 °F to 40 °F | Jan 9 | Jan 5 |
| Oakland | 94601 | 10a | 30 °F to 35 °F | Jan 7 | Dec 23 |
| Bakersfield | 93304 | 9b | 25 °F to 30 °F | Jan 31 | Dec 8 |
| Anaheim | 92808 | 10a | 30 °F to 35 °F | Jan 17 | Dec 19 |
| Stockton | 95204 | 9b | 25 °F to 30 °F | Feb 5 | Dec 8 |
| Riverside | 92506 | 10a | 30 °F to 35 °F | Jan 9 | Dec 25 |
| Santa Clarita | 91350 | 10a | 30 °F to 35 °F | Jan 8 | Jan 1 |
| Modesto | 95351 | 9b | 25 °F to 30 °F | Jan 31 | Dec 5 |
| Oxnard | 93035 | 10b | 35 °F to 40 °F | Dec 29 | Dec 24 |
| Santa Rosa | 95405 | 9a | 20 °F to 25 °F | Feb 25 | Dec 1 |
| Rancho Cucamonga | 91737 | 10a | 30 °F to 35 °F | Jan 4 | Dec 30 |
| Oceanside | 92056 | 10a | 30 °F to 35 °F | Jan 23 | Dec 11 |
| Palmdale | 93552 | 8b | 15 °F to 20 °F | Mar 10 | Nov 19 |
Zone: 2023 USDA ZIP code table for the ZIP code nearest each city's Census center point. Frost dates: 50% (median) dates from the nearest NOAA station, 1991–2020 normals. Cities: the largest California places by 2024 Census population estimates, spread across the state, plus the largest place in each common zone. Large cities can span two half zones.
Which Parts of California Are in Each Zone?
Zone 6a, the coldest California zone with towns, covers <1% of ZIP codes around Mammoth Lakes. Zone 11a, the warmest, covers 1% around Santa Monica, Redondo Beach and Hermosa Beach. The table lists the largest places in every zone.
| Zone | Avg. coldest night | Share of ZIPs | Largest places in this zone |
|---|---|---|---|
| Zone 5b | −15 °F to −10 °F | <1% (1) | Rural ZIP codes only |
| Zone 6a | −10 °F to −5 °F | <1% (7) | Mammoth Lakes |
| Zone 6b | −5 °F to 0 °F | 1% (38) | South Lake Tahoe, Truckee, Alturas, Portola |
| Zone 7a | 0 °F to 5 °F | 2% (41) | Susanville, Bishop |
| Zone 7b | 5 °F to 10 °F | <1% (24) | Big Bear Lake |
| Zone 8a | 10 °F to 15 °F | 1% (38) | Lancaster, Yreka, Mount Shasta, Weed |
| Zone 8b | 15 °F to 20 °F | 4% (112) | Palmdale, Victorville, Hesperia, Apple Valley |
| Zone 9a | 20 °F to 25 °F | 9% (236) | Santa Rosa, Merced, Redding, Hanford |
| Zone 9b | 25 °F to 30 °F | 34% (879) | San Jose, Fresno, Sacramento, Bakersfield |
| Zone 10a | 30 °F to 35 °F | 24% (623) | San Francisco, Oakland, Anaheim, Riverside |
| Zone 10b | 35 °F to 40 °F | 21% (527) | Los Angeles, San Diego, Long Beach, Santa Ana |
| Zone 11a | 40 °F to 45 °F | 1% (28) | Santa Monica, Redondo Beach, Hermosa Beach |
Places: incorporated places with 1,000+ residents, assigned the zone of the ZIP code nearest their Census center point.
What Do the Hardiness Zones Mean for California Gardeners?
A California gardener in zone 11a sees winter lows about 55 °F milder than one in zone 5b, so a shrub or perennial that thrives in one part of the state can die in another. Choose plants rated to your own ZIP code's zone or colder.
Hardiness zones follow latitude, elevation and large bodies of water rather than state lines. Higher ground and inland valleys that trap cold air usually sit in colder half zones, while cities, coasts and large lakes moderate winter lows. Within California, a plant labelled “zones 9–10” survives winter in at least 79% of ZIP codes, but plants at the edge of their range benefit from mulch and a sheltered spot. Enter a ZIP code in the USDA hardiness zone finder by ZIP code to check your exact half zone before buying perennials.
A zone describes winter cold only. Summer heat, humidity, rainfall and soil decide whether a cold-hardy plant thrives, and planting dates for vegetables follow frost dates, not zones: two California towns in the same zone can have last frosts weeks apart.
What Plants Grow Well Across California?
177 plants in PlantoScan's catalogue are hardy in every zone from 9b to 10b, the zones that cover 79% of California ZIP codes. Popular examples include dahlia, spanish flag and arugula.
- DahliaDahlia pinnataPlantoScan
Dahlia
Dahlia pinnata
Zone 8a – 11b
Spanish Flag
Ipomoea lobata
Zone 9a – 12b
AI generated
Arugula
Eruca sativa
Zone 5a – 10b
AI generated
Calla Lily
Zantedeschia aethiopica
Zone 8a – 10b
AI generated
Zinnia
Zinnia elegans
Zone 9a – 13b
ErmellCC BY-SA 4.0Wikimedia Commonsresized
Snapdragon
Antirrhinum majus
Zone 7a – 10b
AI generated
Lemongrass
Cymbopogon citratus
Zone 9b – 12b
AI generated
Gardenia
Gardenia jasminoides
Zone 8a – 11b
AI generated
Bird Of Paradise
Strelitzia reginae
Zone 9b – 11b
AI generated
Hardiness ranges come from PlantoScan's plant database; gardeners in California's colder or warmer edge zones should check each plant's full range.
When Is the Last Frost in California?
Across most California ZIP codes, the average last spring frost falls between January 5 and May 16, from January 2 in San Jose to December 29 in Oxnard. Tender vegetables such as tomatoes go out 1 to 2 weeks after the local date.
The last and first frost dates for California cities include the safer 90% planting date, the fall frost date, growing season length and a tomato planting table for each city. Los Angeles and San Diego have no average frost date at all.
Frequently Asked Questions
- What planting zone is California?
- California spans USDA hardiness zones 5b to 11a on the 2023 USDA Plant Hardiness Zone Map. Zone 9b is the most common, covering 34% of the state's 2,554 ZIP codes, and zones 9b to 10b together cover 79%.
- What hardiness zone is Los Angeles, California?
- Los Angeles is in USDA hardiness zone 10b (ZIP 90034), where the average coldest winter night reaches 35 °F to 40 °F. Frost is essentially absent there in the 1991–2020 NOAA climate normals.
- What hardiness zone is San Diego, California?
- San Diego is in USDA hardiness zone 10b (ZIP 92123), where the average coldest winter night reaches 35 °F to 40 °F. Frost is essentially absent there in the 1991–2020 NOAA climate normals.
- What hardiness zone is San Jose, California?
- San Jose is in USDA hardiness zone 9b (ZIP 95121), where the average coldest winter night reaches 25 °F to 30 °F. Its average last spring frost is January 2 and its first fall frost December 25.
- What is the coldest hardiness zone in California?
- Zone 5b (−15 °F to −10 °F) is the coldest zone in California, found in 1 ZIP code. The warmest is zone 11a (40 °F to 45 °F), around Santa Monica and Redondo Beach.
Zones: 2023 USDA Plant Hardiness Zone Map ZIP code table, USDA Agricultural Research Service and the PRISM Climate Group, Oregon State University, used without changes. Frost dates: NOAA National Centers for Environmental Information, 1991–2020 U.S. Climate Normals. City locations and populations: U.S. Census Bureau Gazetteer files and Vintage 2024 population estimates. PlantoScan is not affiliated with or endorsed by these agencies.