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

Planting zone for 91346 — Mission Hills, CA

ZIP code 91346 (Mission Hills, Los Angeles County) is in USDA zone 10a: the coldest winter night averages 30 to 35 °F.

Where ZIP 91346 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.

Zone10a30 to 35 °F
Coldest night−1.1 to 1.7 °C
Last frostrare
First frostrare
2012 zone10a

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 10a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Mission Hills, 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 Northridge Cal State, CA — 4 miles away, elevation 906 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 91346 came on Jan 17 — 4 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 Mission Hills, CA

The soil mapped at the center of ZIP 91346 is Conejo — clay loam, well drained.

TextureClay loamholds water and nutrients; slow to drain and warm up
pH6.5neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3%moderate
Hydrologic groupCwater soaks in slowly
Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Conejo-Urban land complex, 0 to 2 percent slopes, MLRA 19.

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 91346; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mission Hills, CA

Summer high92 °Faverage high, August
Winter low46 °Faverage low, December
Hot days76days a year at 90 °F or more
Freezing nights1nights a year at 32 °F or less
Growing degree days5,956base 50 °F — the season’s usable heat
Longest day14 h 27 mindaylight on June 21
Shortest day9 h 52 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation14.6 inper year, rain and melted snow

Average high and low, by month

40°50°60°70°80°90°100°January: average high 67 °F, low 47 °F 67°47° JanFebruary: average high 68 °F, low 47 °F 68°47° FebMarch: average high 71 °F, low 49 °F 71°49° MarApril: average high 75 °F, low 52 °F 75°52° AprMay: average high 78 °F, low 56 °F 78°56° MayJune: average high 84 °F, low 60 °F 84°60° JunJuly: average high 90 °F, low 64 °F 90°64° JulAugust: average high 92 °F, low 64 °F 92°64° AugSeptember: average high 89 °F, low 62 °F 89°62° SepOctober: average high 82 °F, low 56 °F 82°56° OctNovember: average high 74 °F, low 50 °F 74°50° NovDecember: average high 67 °F, low 46 °F 67°46° Dec

Precipitation by month inches

0″1″2″3″4″January: 3.42 in precipitation 3.4 JanFebruary: 3.89 in precipitation 3.9 FebMarch: 2.35 in precipitation 2.4 MarApril: 0.72 in precipitation 0.7 AprMay: 0.37 in precipitation 0.4 MayJune: 0.10 in precipitation 0.1 JunJuly: 0.02 in precipitation 0.0 JulAugust: 0.01 in precipitation 0.0 AugSeptember: 0.09 in precipitation 0.1 SepOctober: 0.56 in precipitation 0.6 OctNovember: 0.79 in precipitation 0.8 NovDecember: 2.32 in precipitation 2.3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Northridge Cal State, CA (4 mi away); precipitation: Northridge Cal State, CA (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 10a.

9139510a
Mission Hills, CA · <1 mi
9134510a
Mission Hills, CA · <1 mi
9134310a
North Hills, CA · 2 mi
9139310a
North Hills, CA · 2 mi
9133310a
Pacoima, CA · 2 mi
9133410a
Pacoima, CA · 2 mi
9134110a
San Fernando, CA · 2 mi
9141210a
Panorama City, CA · 2 mi

All 3 ZIP codes in Mission Hills → · California planting zones →

Questions about 91346

What planting zone is ZIP code 91346?

ZIP code 91346 (Mission Hills, CA) is in USDA hardiness zone 10a on the 2023 map: the coldest night of an average winter reaches 30 to 35 °F (−1.1 to 1.7 °C).

How much rain and snow does 91346 get?

About 14.6 inches of precipitation a year (NOAA 1991–2020 normals, Northridge Cal State station).

How hot do summers get in Mission Hills, CA?

The average high peaks at 92 °F in August, with about 76 days a year at 90 °F or more.

What kind of soil does 91346 have?

The USDA soil survey maps Conejo at the center of ZIP 91346: clay loam, well drained, pH about 6.5 (neutral).

Did spring come early in Mission Hills, CA in 2026?

Spring leaf-out near 91346 came on Jan 17 in 2026, 4 days earlier than the 1991–2020 average (Jan 21), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mission Hills, CA?

Intermediate onions: the longest day near 91346 is 14 h 27 min, so day-neutral types bulb best; long-day varieties may not bulb fully.