Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for Santa Ana, CA

Santa Ana, CA is in USDA zone 10b across its 11 ZIP codes.

Santa Ana on the zone map

Outlined: its 6 ZIP code areas · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone10b35 to 40 °F
ZIP codes11
Last frostrare
First frostrare
Growing seasonall year

10b 11 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Santa Ana, CA…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates

A 32 °F frost doesn't happen here in most winters. At the nearest station (NOAA station Tustin Irvine Rch, CA, elevation 236 ft) the median growing season is 365 days. When frost does come, it is a midwinter night or two; cover tender plants when a freeze is forecast.

Frost data: NOAA NCEI U.S. Climate Normals 1991–2020.

When spring arrived in 2026

In 2026, spring leaf-out near 92702 came on Jan 16 — 5 days earlier than the 1991–2020 average (Jan 21).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Soil in Santa Ana, CA

The soil mapped at the center of ZIP 92702 is Chino — silty clay loam, somewhat poorly drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up
pH8.2alkaline; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter2%moderate
Hydrologic groupCwater soaks in slowly
Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Chino silty clay loam, drained.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 92702; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Santa Ana, CA

Summer high85 °Faverage high, August
Winter low48 °Faverage low, December
Hot days30days a year at 90 °F or more
Freezing nights0nights a year at 32 °F or less
Growing degree days5,886base 50 °F — the season’s usable heat
Longest day14 h 24 mindaylight on June 21
Shortest day9 h 54 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation12.5 inper year, rain and melted snow

Average high and low, by month

40°50°60°70°80°90°100°January: average high 69 °F, low 49 °F 69°49° JanFebruary: average high 69 °F, low 50 °F 69°50° FebMarch: average high 71 °F, low 52 °F 71°52° MarApril: average high 73 °F, low 54 °F 73°54° AprMay: average high 75 °F, low 58 °F 75°58° MayJune: average high 78 °F, low 61 °F 78°61° JunJuly: average high 83 °F, low 65 °F 83°65° JulAugust: average high 85 °F, low 65 °F 85°65° AugSeptember: average high 84 °F, low 64 °F 84°64° SepOctober: average high 79 °F, low 59 °F 79°59° OctNovember: average high 74 °F, low 53 °F 74°53° NovDecember: average high 68 °F, low 48 °F 68°48° Dec

Precipitation by month inches

0″1″2″3″4″January: 2.88 in precipitation 2.9 JanFebruary: 3.16 in precipitation 3.2 FebMarch: 1.71 in precipitation 1.7 MarApril: 0.82 in precipitation 0.8 AprMay: 0.29 in precipitation 0.3 MayJune: 0.08 in precipitation 0.1 JunJuly: 0.03 in precipitation 0.0 JulAugust: 0.00 in precipitation 0.0 AugSeptember: 0.12 in precipitation 0.1 SepOctober: 0.50 in precipitation 0.5 OctNovember: 0.79 in precipitation 0.8 NovDecember: 2.16 in precipitation 2.2 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Santa Ana Fire Stn, CA (within 1 mile); precipitation: Santa Ana Fire Stn, CA (within 1 mile). Daylight is calculated from latitude.

ZIP codes in Santa Ana

California planting zones →

Questions about Santa Ana

What planting zone is Santa Ana, CA?

Santa Ana, CA is in USDA hardiness zone 10b on the 2023 map (10b: 35 to 40 °F).

What kind of onions grow in Santa Ana, CA?

Intermediate onions: the longest day is 14 h 24 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

How much rain and snow does Santa Ana, CA get?

About 12.5 inches of precipitation a year (NOAA 1991–2020 normals).