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

Planting zone for 92092 — La Jolla, CA

ZIP code 92092 (La Jolla, San Diego County) is in USDA zone 10b: the coldest winter night averages 35 to 40 °F.

Where ZIP 92092 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 zone10a

Was 10a 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 10b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for La Jolla, 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 Rancho Bernardo, CA — 14 miles away, elevation 689 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 92092 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 La Jolla, CA

The soil mapped at the center of ZIP 92092 is Chesterton — fine sandy loam, moderately well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding
pH5.8moderately acidic; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter0.75%low — add compost
Hydrologic groupDwater soaks in very slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Chesterton fine sandy loam, 2 to 5 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 92092; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in La Jolla, 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
Precipitation12.3 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″4″January: 2.33 in precipitation 2.3 JanFebruary: 3.03 in precipitation 3.0 FebMarch: 1.88 in precipitation 1.9 MarApril: 0.94 in precipitation 0.9 AprMay: 0.36 in precipitation 0.4 MayJune: 0.08 in precipitation 0.1 JunJuly: 0.12 in precipitation 0.1 JulAugust: 0.03 in precipitation 0.0 AugSeptember: 0.14 in precipitation 0.1 SepOctober: 0.50 in precipitation 0.5 OctNovember: 0.97 in precipitation 1.0 NovDecember: 1.89 in precipitation 1.9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: San Diego Miramar NAS, CA (6 mi away); precipitation: San Diego 9.5 Nnw, CA (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

All 5 ZIP codes in La Jolla → · California planting zones →

Questions about 92092

What planting zone is ZIP code 92092?

ZIP code 92092 (La Jolla, 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 92092 get?

About 12.3 inches of precipitation a year (NOAA 1991–2020 normals, San Diego 9.5 Nnw station).

How hot do summers get in La Jolla, 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 92092 have?

The USDA soil survey maps Chesterton at the center of ZIP 92092: fine sandy loam, moderately well drained, pH about 5.8 (moderately acidic).

Did spring come early in La Jolla, CA in 2026?

Spring leaf-out near 92092 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 La Jolla, CA?

Intermediate onions: the longest day near 92092 is 14 h 19 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 92092 change?

Yes. The 2012 USDA map put 92092 in zone 10a; the 2023 map puts it in zone 10b. The newer map uses 1991–2020 data and more weather stations.