Planting zone for 92352 — Lake Arrowhead, CA
ZIP code 92352 (Lake Arrowhead, San Bernardino County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is May 5 and the first fall frost November 2.
Where ZIP 92352 is
Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoomNot 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.
Was 8a 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 8b means →
Frost forecast — next 7 nights
live from the National Weather ServiceLoading the forecast for Lake Arrowhead, 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 in Lake Arrowhead, CA
A hard freeze (28 °F) usually ends around April 11 and returns around November 16.
From the NOAA station Lake Arrowhead, CA — within 1 mile, elevation 5,207 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.
When to plant vegetables in 92352
Counted from the median last spring frost (May 5) and first fall frost (Nov 2) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.
When spring arrived in 2026
In 2026, spring leaf-out near 92352 came on Feb 3 — 21 days earlier than the 1991–2020 average (Feb 24).
Feb 242026
Feb 3
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 Lake Arrowhead, CA
The soil mapped at the center of ZIP 92352 is Cedarpines — cobbly sandy loam, well drained.
Map unit: Cedarpines-Stargazer-Urban land complex, 9 to 15 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 92352; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.
Climate in Lake Arrowhead, CA
Average high and low, by month
Precipitation by month inches · ❄ = snowfall
NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Lake Arrowhead, CA (within 1 mile); precipitation: Lake Arrowhead, CA (within 1 mile). Daylight is calculated from latitude.
Nearby ZIP codes
7 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.
Questions about 92352
What planting zone is ZIP code 92352?
ZIP code 92352 (Lake Arrowhead, CA) is in USDA hardiness zone 8b on the 2023 map: the coldest night of an average winter reaches 15 to 20 °F (−9.4 to −6.7 °C).
When is the last frost in Lake Arrowhead, CA?
The median last spring frost (32 °F) near 92352 is May 5; after May 31 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Lake Arrowhead station.
When is the first frost in Lake Arrowhead, CA?
The median first fall frost near 92352 is November 2, giving a median frost-free growing season of 176 days.
When should I plant tomatoes in 92352?
Start tomato seeds indoors around Mar 10 – Mar 24 and set transplants outside around May 12 – May 26, one to three weeks after the median last frost.
How much rain and snow does 92352 get?
About 37.7 inches of precipitation a year and 22 inches of snowfall (NOAA 1991–2020 normals, Lake Arrowhead station).
How hot do summers get in Lake Arrowhead, CA?
The average high peaks at 82 °F in August, with about 11 days a year at 90 °F or more.
What kind of soil does 92352 have?
The USDA soil survey maps Cedarpines at the center of ZIP 92352: cobbly sandy loam, well drained, pH about 6.4 (slightly acidic).
Did spring come early in Lake Arrowhead, CA in 2026?
Spring leaf-out near 92352 came on Feb 3 in 2026, 21 days earlier than the 1991–2020 average (Feb 24), according to the USA National Phenology Network Spring Index.
What kind of onions grow in Lake Arrowhead, CA?
Intermediate onions: the longest day near 92352 is 14 h 27 min, so day-neutral types bulb best; long-day varieties may not bulb fully.
Did the zone for 92352 change?
Yes. The 2012 USDA map put 92352 in zone 8a; the 2023 map puts it in zone 8b. The newer map uses 1991–2020 data and more weather stations.