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

Planting zone for 90717 — Lomita, CA

ZIP code 90717 (Lomita, Los Angeles County) is in USDA zone 10b: the coldest winter night averages 35 to 40 °F.

Where ZIP 90717 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 Lomita, 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 Torrance Airport, CA — within 1 mile, elevation 89 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 90717 came on Jan 17 — 3 days earlier than the 1991–2020 average (Jan 20).

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 Lomita, CA

The soil mapped at the center of ZIP 90717 is Anthraltic Xerorthents — loam, well drained. Much of the area is built over (urban land); this is the natural soil underneath.

TextureLoama good balance for most vegetables
pH7.4slightly alkaline; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter1.5%low — add compost
Hydrologic groupCwater soaks in slowly
Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Urban land-Anthraltic Xerorthents, loamy substratum-Grommet complex, 0 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 90717; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Lomita, CA

Summer high78 °Faverage high, August
Winter low46 °Faverage low, December
Hot days6days a year at 90 °F or more
Freezing nights1nights a year at 32 °F or less
Growing degree days4,760base 50 °F — the season’s usable heat
Longest day14 h 24 mindaylight on June 21
Shortest day9 h 54 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation14.2 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 66 °F, low 48 °F 66°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 55 °F 72°55° MayJune: average high 74 °F, low 59 °F 74°59° JunJuly: average high 77 °F, low 62 °F 77°62° JulAugust: average high 78 °F, low 62 °F 78°62° AugSeptember: average high 78 °F, low 61 °F 78°61° SepOctober: average high 76 °F, low 57 °F 76°57° OctNovember: average high 71 °F, low 51 °F 71°51° NovDecember: average high 66 °F, low 46 °F 66°46° Dec

Precipitation by month inches

0″1″2″3″4″January: 3.44 in precipitation 3.4 JanFebruary: 3.71 in precipitation 3.7 FebMarch: 2.01 in precipitation 2.0 MarApril: 0.66 in precipitation 0.7 AprMay: 0.33 in precipitation 0.3 MayJune: 0.08 in precipitation 0.1 JunJuly: 0.05 in precipitation 0.1 JulAugust: 0.01 in precipitation 0.0 AugSeptember: 0.10 in precipitation 0.1 SepOctober: 0.55 in precipitation 0.6 OctNovember: 0.88 in precipitation 0.9 NovDecember: 2.41 in precipitation 2.4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Torrance Airport, CA (within 1 mile); precipitation: Torrance 2.8 Sw, CA (within 1 mile). 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.

California planting zones →

Questions about 90717

What planting zone is ZIP code 90717?

ZIP code 90717 (Lomita, 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 90717 get?

About 14.2 inches of precipitation a year (NOAA 1991–2020 normals, Torrance 2.8 Sw station).

How hot do summers get in Lomita, CA?

The average high peaks at 78 °F in August, with about 6 days a year at 90 °F or more.

What kind of soil does 90717 have?

The USDA soil survey maps Anthraltic Xerorthents at the center of ZIP 90717: loam, well drained, pH about 7.4 (slightly alkaline).

Did spring come early in Lomita, CA in 2026?

Spring leaf-out near 90717 came on Jan 17 in 2026, 3 days earlier than the 1991–2020 average (Jan 20), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Lomita, CA?

Intermediate onions: the longest day near 90717 is 14 h 24 min, so day-neutral types bulb best; long-day varieties may not bulb fully.