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

Planting zone for 92106 — San Diego, CA

ZIP code 92106 (San Diego, San Diego County) is in USDA zone 10b: the coldest winter night averages 35 to 40 °F.

Where ZIP 92106 is

Outlined: the ZIP code area · 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
Coldest night1.7 to 4.4 °C
Last frostrare
First frostrare
2012 zone10b

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 10b 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 San Diego Brown Field, CA — 18 miles away, elevation 515 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 92106 came on Jan 19 — about the same time as 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 92106 is Reiff — fine sandy loam, well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding
pH7.3neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter0.75%low — add compost
Hydrologic groupAwater soaks in fast
Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Reiff fine sandy loam, 0 to 2 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 92106; 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 high77 °Faverage high, August
Winter low49 °Faverage low, January
Hot days4days a year at 90 °F or more
Freezing nights0nights a year at 32 °F or less
Growing degree days5,094base 50 °F — the season’s usable heat
Longest day14 h 18 mindaylight on June 21
Shortest day10 h 00 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation10.8 inper year, rain and melted snow

Average high and low, by month

40°50°60°70°80°90°January: average high 66 °F, low 49 °F 66°49° JanFebruary: average high 66 °F, low 51 °F 66°51° FebMarch: average high 67 °F, low 53 °F 67°53° MarApril: average high 68 °F, low 55 °F 68°55° AprMay: average high 69 °F, low 59 °F 69°59° MayJune: average high 71 °F, low 62 °F 71°62° JunJuly: average high 74 °F, low 65 °F 74°65° JulAugust: average high 77 °F, low 67 °F 77°67° AugSeptember: average high 77 °F, low 65 °F 77°65° SepOctober: average high 75 °F, low 60 °F 75°60° OctNovember: average high 71 °F, low 54 °F 71°54° NovDecember: average high 66 °F, low 49 °F 66°49° Dec

Precipitation by month inches

0″1″2″3″January: 1.97 in precipitation 2.0 JanFebruary: 2.68 in precipitation 2.7 FebMarch: 1.63 in precipitation 1.6 MarApril: 0.78 in precipitation 0.8 AprMay: 0.32 in precipitation 0.3 MayJune: 0.10 in precipitation 0.1 JunJuly: 0.09 in precipitation 0.1 JulAugust: 0.02 in precipitation 0.0 AugSeptember: 0.16 in precipitation 0.2 SepOctober: 0.50 in precipitation 0.5 OctNovember: 0.79 in precipitation 0.8 NovDecember: 1.76 in precipitation 1.8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: North Island NAS, CA (2 mi away); precipitation: San Diego 5.2wnw, CA (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

5 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 92106

What planting zone is ZIP code 92106?

ZIP code 92106 (San Diego, CA) is in USDA hardiness zone 10b on the 2023 map: the coldest night of an average winter reaches 35 to 40 °F (1.7 to 4.4 °C).

How much rain and snow does 92106 get?

About 10.8 inches of precipitation a year (NOAA 1991–2020 normals, San Diego 5.2wnw station).

How hot do summers get in San Diego, CA?

The average high peaks at 77 °F in August, with about 4 days a year at 90 °F or more.

What kind of soil does 92106 have?

The USDA soil survey maps Reiff at the center of ZIP 92106: fine sandy loam, well drained, pH about 7.3 (neutral).

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

Spring leaf-out near 92106 came on Jan 19 in 2026, about the same as 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 92106 is 14 h 18 min, so day-neutral types bulb best; long-day varieties may not bulb fully.