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

Planting zone for Mission Viejo, CA

Mission Viejo, CA is in USDA zone 10b across its 3 ZIP codes.

Mission Viejo on the zone map

Outlined: its 2 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 codes3
Last frostrare
First frostrare
Growing seasonall year

10b 3 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Mission Viejo, 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 92690 came on Jan 16 — 3 days earlier than the 1991–2020 average (Jan 19).

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 Mission Viejo, CA

The soil mapped at the center of ZIP 92690 is Bosanko — clay, well drained.

TextureClayholds water and nutrients; slow to drain and warm up
pH7.3neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter1.5%low — add compost
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Bosanko-Balcom complex, 15 to 30 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 92690; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mission Viejo, CA

Summer high90 °Faverage high, August
Winter low48 °Faverage low, February
Hot days62days a year at 90 °F or more
Freezing nights1nights a year at 32 °F or less
Growing degree days6,135base 50 °F — the season’s usable heat
Longest day14 h 23 mindaylight on June 21
Shortest day9 h 55 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

40°50°60°70°80°90°100°January: average high 69 °F, low 49 °F 69°49° JanFebruary: average high 71 °F, low 48 °F 71°48° FebMarch: average high 73 °F, low 50 °F 73°50° MarApril: average high 76 °F, low 52 °F 76°52° AprMay: average high 79 °F, low 56 °F 79°56° MayJune: average high 83 °F, low 59 °F 83°59° JunJuly: average high 88 °F, low 62 °F 88°62° JulAugust: average high 90 °F, low 62 °F 90°62° AugSeptember: average high 89 °F, low 62 °F 89°62° SepOctober: average high 84 °F, low 58 °F 84°58° OctNovember: average high 76 °F, low 53 °F 76°53° NovDecember: average high 68 °F, low 48 °F 68°48° 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: Irvine Rch, CA (9 mi away); precipitation: Mission Viejo 1.3 Sse, CA (within 1 mile). Daylight is calculated from latitude.

ZIP codes in Mission Viejo

California planting zones →

Questions about Mission Viejo

What planting zone is Mission Viejo, CA?

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

What kind of onions grow in Mission Viejo, 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 Mission Viejo, CA get?

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