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

Planting zone for 92137 — San Diego, CA

ZIP code 92137 (San Diego, San Diego County) is in USDA zone 11a: the coldest winter night averages 40 to 45 °F.

Where ZIP 92137 is

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.

Zone11a40 to 45 °F
Coldest night4.4 to 7.2 °C
Last frostrare
First frostrare
2012 zone10b

Was 10b on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 11a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for San Diego, 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 El Cajon, CA — 12 miles away, elevation 495 ft) the median growing season is 350 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 92137 came on Jan 18 — 3 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 San Diego, CA

The soil mapped at the center of ZIP 92137 is Redding — gravelly loam, well drained.

TextureGravelly loama good balance for most vegetables
pH5.6moderately acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter1.25%low — add compost
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Redding gravelly loam, 2 to 9 percent slopes.

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 92137; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in San Diego, CA

Summer high82 °Faverage high, August
Winter low46 °Faverage low, December
Hot days20days a year at 90 °F or more
Freezing nights0nights a year at 32 °F or less
Growing degree days5,208base 50 °F — the season’s usable heat
Longest day14 h 19 mindaylight on June 21
Shortest day9 h 59 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation11.5 inper year, rain and melted snow

Average high and low, by month

40°50°60°70°80°90°January: average high 67 °F, low 47 °F 67°47° JanFebruary: average high 67 °F, low 48 °F 67°48° FebMarch: average high 68 °F, low 50 °F 68°50° MarApril: average high 70 °F, low 52 °F 70°52° AprMay: average high 72 °F, low 57 °F 72°57° MayJune: average high 75 °F, low 60 °F 75°60° JunJuly: average high 80 °F, low 64 °F 80°64° JulAugust: average high 82 °F, low 65 °F 82°65° AugSeptember: average high 82 °F, low 63 °F 82°63° SepOctober: average high 78 °F, low 58 °F 78°58° OctNovember: average high 72 °F, low 51 °F 72°51° NovDecember: average high 67 °F, low 46 °F 67°46° Dec

Precipitation by month inches

0″1″2″3″January: 2.30 in precipitation 2.3 JanFebruary: 2.66 in precipitation 2.7 FebMarch: 1.64 in precipitation 1.6 MarApril: 0.78 in precipitation 0.8 AprMay: 0.28 in precipitation 0.3 MayJune: 0.05 in precipitation 0.1 JunJuly: 0.12 in precipitation 0.1 JulAugust: 0.02 in precipitation 0.0 AugSeptember: 0.14 in precipitation 0.1 SepOctober: 0.57 in precipitation 0.6 OctNovember: 0.93 in precipitation 0.9 NovDecember: 1.99 in precipitation 2.0 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: San Diego Miramar NAS, CA (within 1 mile); precipitation: San Diego Miramar NAS, CA (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

8 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

All 73 ZIP codes in San Diego → · California planting zones →

Questions about 92137

What planting zone is ZIP code 92137?

ZIP code 92137 (San Diego, CA) is in USDA hardiness zone 11a on the 2023 map: the coldest night of an average winter reaches 40 to 45 °F (4.4 to 7.2 °C).

How much rain and snow does 92137 get?

About 11.5 inches of precipitation a year (NOAA 1991–2020 normals, San Diego Miramar NAS station).

How hot do summers get in San Diego, CA?

The average high peaks at 82 °F in August, with about 20 days a year at 90 °F or more.

What kind of soil does 92137 have?

The USDA soil survey maps Redding at the center of ZIP 92137: gravelly loam, well drained, pH about 5.6 (moderately acidic).

Did spring come early in San Diego, CA in 2026?

Spring leaf-out near 92137 came on Jan 18 in 2026, 3 days earlier than the 1991–2020 average (Jan 21), according to the USA National Phenology Network Spring Index.

What kind of onions grow in San Diego, CA?

Intermediate onions: the longest day near 92137 is 14 h 19 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 92137 change?

Yes. The 2012 USDA map put 92137 in zone 10b; the 2023 map puts it in zone 11a. The newer map uses 1991–2020 data and more weather stations.