Santa Maria, California: planting zone & frost dates
Santa Maria is in USDA plant hardiness zone 9b, where the average coldest winter night reaches 25 to 30°F (-3.9 to -1.1°C). The typical last spring frost is around Feb 18 and the first fall frost around Dec 5.
Frost dates
| Probability | Last spring frost (32°F) | First fall frost (32°F) |
|---|---|---|
| Safer (10% risk) | Mar 16 | Nov 21 |
| Typical planning date (30% risk) | Feb 18 | Dec 5 |
| Median (50%) | Feb 4 | Dec 13 |
How to read this: after the spring "10% risk" date, a 32°F frost happens in only about 1 year in 10. In fall, the "10% risk" date is the early end — a frost before it happens about 1 year in 10.
Frost data comes from NOAA station SANTA MARIA PUBLIC AP, CA (USW00023273), 2.4 mi (3.8 km) from the city center and 36 ft higher than the city center (+11 m). Record used for the 1991–2020 normals: 24 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Santa Maria
All 3 ZIP codes covering Santa Maria are in zone 9b.
Vegetable planting calendar for Santa Maria
Dates are counted from the 30%-risk frost dates above (last frost Feb 18, first frost Dec 5). Shift a week later in cold spots or low-lying ground.
| Crop | Start indoors | Transplant / plant out | Direct sow | Fall crop sow/plant |
|---|---|---|---|---|
| Tomato | Dec 24 – Jan 7 | Feb 25 – Mar 11 | — | — |
| Pepper | Dec 10 – Dec 24 | Mar 4 – Mar 18 | — | — |
| Lettuce Mild winters: fall and winter plantings are usually more reliable than spring. | Jan 7 – Jan 21 | Feb 4 – Feb 25 | Jan 21 – Mar 4 | Sep 26 – Oct 24 |
| Green Beans | — | — | Feb 25 – Apr 1 | Sep 12 – Sep 26 |
| Sweet Corn | — | — | Feb 25 – Mar 25 | — |
| Zucchini & Summer Squash | Jan 21 – Jan 28 | Feb 25 – Mar 11 | Feb 25 – Mar 18 | Sep 12 – Sep 26 |
| Cucumber | Jan 21 – Jan 28 | Mar 4 – Mar 11 | Feb 25 – Mar 18 | Sep 12 – Sep 26 |
| Carrot Mild winters: fall and winter plantings are usually more reliable than spring. | — | — | Jan 28 – Mar 4 | Sep 12 – Sep 26 |
| Onion Mild winters: fall and winter plantings are usually more reliable than spring. | Nov 26 – Dec 10 | Jan 21 – Feb 4 | — | — |
| Potato Mild winters: fall and winter plantings are usually more reliable than spring. | — | Jan 21 – Feb 11 | — | — |
| Basil | Jan 7 – Jan 21 | Mar 4 – Mar 18 | Mar 4 – Mar 25 | — |
| Spinach Mild winters: fall and winter plantings are usually more reliable than spring. | — | — | Jan 7 – Feb 4 | Oct 10 – Nov 7 |
| Kale Mild winters: fall and winter plantings are usually more reliable than spring. | Dec 24 – Jan 7 | Jan 21 – Feb 11 | Jan 21 – Feb 11 | Sep 26 – Oct 24 |
| Broccoli Mild winters: fall and winter plantings are usually more reliable than spring. | Dec 24 – Jan 7 | Feb 4 – Feb 25 | — | Sep 12 – Sep 26 |
| Peas Mild winters: fall and winter plantings are usually more reliable than spring. | — | — | Jan 7 – Jan 28 | Sep 26 – Oct 10 |
| Eggplant | Dec 10 – Dec 24 | Mar 4 – Mar 18 | — | — |
| Cabbage Mild winters: fall and winter plantings are usually more reliable than spring. | Dec 24 – Jan 7 | Jan 21 – Feb 4 | — | Sep 12 – Sep 26 |
| Radish Mild winters: fall and winter plantings are usually more reliable than spring. | — | — | Jan 14 – Mar 4 | Oct 24 – Nov 21 |
| Strawberry | — | Jan 21 – Feb 11 | — | — |
| Beets Mild winters: fall and winter plantings are usually more reliable than spring. | — | — | Jan 28 – Mar 11 | Sep 26 – Oct 10 |
Nearby cities in California
- Santa Barbara — zone 10b, last frost Jan 27, first frost Dec 29
- Ventura — zone 10a, frost rare
- Oxnard — zone 10b, frost rare
- Bakersfield — zone 9b, last frost Feb 12, first frost Dec 1
- Thousand Oaks — zone 10a, last frost Feb 12, first frost Dec 6
- Visalia — zone 9b, last frost Feb 2, first frost Dec 6
More: all California cities · other zone 9b cities: Houston, TX, Phoenix, AZ, Jacksonville, FL, San Jose, CA, Fresno, CA, Sacramento, CA, Mesa, AZ, Bakersfield, CA
Santa Maria gardening questions
When is the last frost in Santa Maria, CA?
Plan around Feb 18. At NOAA's Santa Maria Public Airport, CA station, 2.4 mi from the city center, there is a 30% chance of a 32°F frost after that date. Half of springs have their last frost by Feb 4, and after Mar 16 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Jan 5. Springs here are erratic: 77 days separate the 90% and 10% dates, versus a median of 36 days for cities on this site, so watch the forecast rather than the calendar.
When should I plant tomatoes in Santa Maria, CA?
Start seeds indoors Dec 24 – Jan 7 and set transplants outside Feb 25 – Mar 11, once nights stay above 50°F and the soil is near 60°F. With about 290 frost-free days, frost is not the main limit — fruit set drops when nights stay above about 75°F, so early plantings tend to do best. More: tomato planting dates by zone.
How long is the growing season in Santa Maria?
About 315 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 268 days, and in 1 year in 10 it runs 354 days or more. In fall there is a 10% chance of frost by Nov 21 and a 30% chance by Dec 5. That ranks 63rd longest of 84 California cities on this site.
When should I plant a fall garden in Santa Maria?
Count back from the first fall frost (Dec 5): transplant broccoli Sep 12 – Sep 26; sow kale Sep 26 – Oct 24; sow lettuce Sep 26 – Oct 24; sow radishes Oct 24 – Nov 21. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Dec 27. How the math works: succession and fall planting.
Did Santa Maria's hardiness zone change on the 2023 map?
No. Going by the zone that covers most of the city's land, Santa Maria is zone 9b 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.
How does Santa Maria compare with Santa Barbara, CA?
Santa Maria is zone 9b and Santa Barbara is zone 10b. The typical last spring frost in Santa Maria (Feb 18) comes about 22 days later than in Santa Barbara, CA (Jan 27), 55 miles away, and the first fall frost is Dec 5 versus Dec 29. The two cities use different NOAA stations.