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

Planting zone for San Juan Capistrano, CA

San Juan Capistrano, CA is in USDA zone 10b across its 2 ZIP codes.

San Juan Capistrano on the zone map

Outlined: its 1 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 codes2
Last frostrare
First frostrare
Growing seasonall year

10b 2 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for San Juan Capistrano, 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 Laguna Beach, CA, elevation 43 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 92675 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 Juan Capistrano, CA

The soil mapped at the center of ZIP 92675 is Corralitos — loamy sand, somewhat excessively drained.

TextureLoamy sanddrains and warms fast; dries out and needs more feeding
pH6.5neutral; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter1.25%low — add compost
Hydrologic groupAwater soaks in fast
Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Corralitos loamy sand.

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 92675; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in San Juan Capistrano, CA

Summer high81 °Faverage high, August
Winter low44 °Faverage low, January
Hot days4days a year at 90 °F or more
Freezing nights1nights a year at 32 °F or less
Growing degree days4,786base 50 °F — the season’s usable heat
Longest day14 h 23 mindaylight on June 21
Shortest day9 h 56 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation15.3 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°32 °FJanuary: average high 68 °F, low 44 °F 68°44° JanFebruary: average high 68 °F, low 45 °F 68°45° FebMarch: average high 69 °F, low 48 °F 69°48° MarApril: average high 73 °F, low 50 °F 73°50° AprMay: average high 75 °F, low 55 °F 75°55° MayJune: average high 76 °F, low 58 °F 76°58° JunJuly: average high 80 °F, low 60 °F 80°60° JulAugust: average high 81 °F, low 61 °F 81°61° AugSeptember: average high 81 °F, low 59 °F 81°59° SepOctober: average high 77 °F, low 55 °F 77°55° OctNovember: average high 72 °F, low 49 °F 72°49° NovDecember: average high 67 °F, low 44 °F 67°44° Dec

Precipitation by month inches

0″1″2″3″4″January: 3.47 in precipitation 3.5 JanFebruary: 3.69 in precipitation 3.7 FebMarch: 1.98 in precipitation 2.0 MarApril: 0.88 in precipitation 0.9 AprMay: 0.45 in precipitation 0.5 MayJune: 0.09 in precipitation 0.1 JunJuly: 0.07 in precipitation 0.1 JulAugust: 0.01 in precipitation 0.0 AugSeptember: 0.14 in precipitation 0.1 SepOctober: 1.11 in precipitation 1.1 OctNovember: 1.10 in precipitation 1.1 NovDecember: 2.26 in precipitation 2.3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Laguna Beach, CA (8 mi away); precipitation: Mission Viejo 1.3 Sse, CA (7 mi away). Daylight is calculated from latitude.

ZIP codes in San Juan Capistrano

California planting zones →

Questions about San Juan Capistrano

What planting zone is San Juan Capistrano, CA?

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

What kind of onions grow in San Juan Capistrano, CA?

Intermediate onions: the longest day is 14 h 23 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

How much rain and snow does San Juan Capistrano, CA get?

About 15.3 inches of precipitation a year (NOAA 1991–2020 normals).