San Francisco, California: planting zone & frost dates
San Francisco is in USDA plant hardiness zone 10b, where the average coldest winter night reaches 35 to 40°F (1.7 to 4.4°C). Frost is rare here.
Frost dates
Frost data comes from NOAA station SAN FRANCISCO DWTN, CA (USW00023272), 0.7 mi (1.2 km) from the city center and 89 ft higher than the city center (+27 m). Record used for the 1991–2020 normals: 29 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across San Francisco
San Francisco spans more than one half-zone. Share of the city's land area by zone (via its 28 ZIP codes): 10b (96%), 10a (4%). The headline zone is the one covering the most land. Look up your ZIP for your exact zone.
ZIP codes in San Francisco and their zones
| ZIP | Zone | Share of city land |
|---|---|---|
| 94124 | 10b | 10.2% |
| 94112 | 10b | 7.1% |
| 94122 | 10b | 6.9% |
| 94132 | 10b | 6.7% |
| 94134 | 10b | 5.5% |
| 94116 | 10b | 5.4% |
| 94121 | 10b | 5.4% |
| 94110 | 10b | 5.1% |
| 94129 | 10b | 5.0% |
| 94118 | 10b | 4.3% |
| 94131 | 10b | 4.3% |
| 94107 | 10b | 4.0% |
| 94127 | 10a | 4.0% |
| 94114 | 10b | 3.0% |
| 94103 | 10b | 2.9% |
| 94117 | 10b | 2.7% |
| 94115 | 10b | 2.4% |
| 94109 | 10b | 2.3% |
| 94123 | 10b | 2.3% |
| 94130 | 10b | 1.9% |
| 94102 | 10b | 1.4% |
| 94133 | 10b | 1.4% |
| 94158 | 10b | 1.3% |
| 94105 | 10b | 1.1% |
| 94111 | 10b | 0.7% |
| 94108 | 10b | 0.5% |
| 94104 | 10b | 0.2% |
| 94188 | 10b | 0.2% |
Vegetable planting calendar for San Francisco
Windows below are for a frost-free climate: plant cool-season crops from fall through late winter and warm-season crops in late winter–spring, with a second warm-season round in late summer for some crops.
| Crop | Planting windows (frost-free climate) | |||
|---|---|---|---|---|
| Tomato | Jan 15 – Mar 31; Aug 1 – Sep 15 | |||
| Pepper | Feb 1 – Apr 15; Jul 15 – Aug 31 | |||
| Lettuce | Sep 15 – Feb 15 | |||
| Green Beans | Feb 15 – Apr 30; Aug 15 – Sep 30 | |||
| Sweet Corn | Feb 15 – Apr 15; Aug 1 – Aug 31 | |||
| Zucchini & Summer Squash | Feb 15 – Apr 15; Aug 1 – Sep 15 | |||
| Cucumber | Feb 15 – Apr 15; Aug 1 – Sep 15 | |||
| Carrot | Sep 1 – Feb 28 | |||
| Onion | Oct 15 – Jan 15 | |||
| Potato | Jan 1 – Feb 28; Sep 1 – Oct 15 | |||
| Basil | Mar 1 – Jun 30; Aug 15 – Sep 30 | |||
| Spinach | Oct 1 – Feb 15 | |||
| Kale | Sep 1 – Feb 15 | |||
| Broccoli | Sep 1 – Jan 15 | |||
| Peas | Oct 1 – Jan 31 | |||
| Eggplant | Feb 15 – Apr 30; Jul 15 – Aug 31 | |||
| Cabbage | Sep 1 – Jan 31 | |||
| Radish | Sep 15 – Mar 15 | |||
| Strawberry | Oct 1 – Nov 30 | |||
| Beets | Sep 15 – Feb 28 | |||
Nearby cities in California
- Daly City — zone 10a, last frost Jan 23, first frost Dec 12
- Berkeley — zone 10a, last frost Jan 12, first frost Dec 25
- Alameda — zone 10a, last frost Jan 22, first frost Dec 10
- Richmond — zone 10a, last frost Jan 14, first frost Dec 27
- Oakland — zone 10a, frost rare
- San Mateo — zone 10a, last frost Jan 3, first frost Dec 21
More: all California cities · other zone 10b cities: San Diego, CA, Long Beach, CA, Anaheim, CA, Irvine, CA, Santa Ana, CA, Chula Vista, CA, St. Petersburg, FL, Cape Coral, FL
San Francisco gardening questions
Does it ever frost in San Francisco, CA?
Rarely. From 1991 to 2020, NOAA's San Francisco Dwtn, CA station, 0.7 mi from the city center, did not reach 32°F at all — too seldom for NOAA to compute frost dates. Zone 10b means the coldest night of an average winter is 35 to 40°F (1.7 to 4.4°C), so frost is essentially unknown, though cool nights can slow tropical plants.
When should I plant tomatoes in San Francisco, CA?
Without a frost season, plant by temperature: set out tomatoes Jan 15 – Mar 31 and Aug 1 – Sep 15. Fruit set drops when nights stay above about 75°F, so avoid timing harvests for the hottest weeks. More: tomato planting by zone.
When is the best time for lettuce and broccoli in San Francisco?
Cool-season crops do best in the mild months: plant lettuce Sep 15 – Feb 15 and broccoli Sep 1 – Jan 15. Summer heat makes lettuce bolt and broccoli flower early.
Did San Francisco's hardiness zone change on the 2023 map?
No. Going by the zone that covers most of the city's land, San Francisco is zone 10b on both the 2012 and the 2023 USDA maps (PRISM/OSU ZIP listings). About 42% of U.S. ZIP codes kept their half-zone in 2023. Why the 2023 map is warmer.
Is all of San Francisco in zone 10b?
No. Zone 10b covers about 96% of the city's land; the rest is in 10a (4%), measured across the city's 28 ZIP codes. Check your own ZIP code in the table above or with the ZIP lookup.
How does San Francisco compare with Daly City, CA?
San Francisco is zone 10b and Daly City is zone 10a. Frost is rare in San Francisco, but Daly City (6 miles away) has a typical last frost around Jan 23 — see Daly City, CA.