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

Planting zone for 92256 — Morongo Valley, CA

ZIP code 92256 (Morongo Valley, San Bernardino County) is in USDA zone 9b: the coldest winter night averages 25 to 30 °F. The median last spring frost is February 25 and the first fall frost December 15.

Where ZIP 92256 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.

Zone9b25 to 30 °F
Coldest night−3.9 to −1.1 °C
Last frostFeb 25
First frostDec 15
2012 zone9a

Was 9a 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 9b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Morongo Valley, 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 Morongo Valley, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostFebruary 25median — 50% chance of a later frost
Safe for tender plantsApril 3only 10% chance of frost after
First fall frostDecember 15median — 10% chance by Nov 23
Growing season297 daysfrost-free, median

A hard freeze (28 °F) usually ends around January 25 and returns around January 6.

From the NOAA station Morongo Valley N, CA — 3 miles away, elevation 3,146 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 92256

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Jan 14 – Jan 28
SpinachSow outdoors · Jan 14 – Feb 4
Broccoli, cabbageStart indoors · Dec 17 – Dec 31
Broccoli, cabbageTransplant · Feb 4 – Feb 18
Onion setsPlant outdoors · Jan 28 – Feb 11
PotatoesPlant outdoors · Feb 4 – Feb 18
LettuceSow outdoors · Jan 28 – Feb 11
Carrots, beetsSow outdoors · Feb 4 – Feb 18
TomatoesStart indoors · Dec 31 – Jan 14
TomatoesTransplant · Mar 4 – Mar 18
Peppers, eggplantStart indoors · Dec 17 – Dec 31
Peppers, eggplantTransplant · Mar 11 – Mar 25
BeansSow outdoors · Mar 4 – Mar 18
Sweet cornSow outdoors · Mar 4 – Mar 18
Cucumbers, squashSow outdoors · Mar 4 – Mar 18
Fall lettuce, spinachSow outdoors · Oct 20 – Nov 3
GarlicPlant cloves · Dec 1 – Jan 5
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 25) and first fall frost (Dec 15) 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 92256 came on Jan 24 — 13 days earlier than the 1991–2020 average (Feb 6).

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 Morongo Valley, CA

The soil mapped at the center of ZIP 92256 is Typic Haplargids — cobbly fine sandy loam, well drained.

TextureCobbly fine sandy loamdrains and warms fast; dries out and needs more feeding
pH7.5slightly alkaline; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter0.2%low — add compost
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Typic Haplargids and Lithic Haplargids; thermic hills and mountains.

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 92256; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Morongo Valley, CA

Summer high94 °Faverage high, July
Winter low40 °Faverage low, December
Hot days91days a year at 90 °F or more
Freezing nights13nights a year at 32 °F or less
Growing degree days5,671base 50 °F — the season’s usable heat
Longest day14 h 26 mindaylight on June 21
Shortest day9 h 53 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation9.4 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°100°32 °FJanuary: average high 59 °F, low 41 °F 59°41° JanFebruary: average high 61 °F, low 42 °F 61°42° FebMarch: average high 66 °F, low 45 °F 66°45° MarApril: average high 73 °F, low 48 °F 73°48° AprMay: average high 80 °F, low 54 °F 80°54° MayJune: average high 89 °F, low 63 °F 89°63° JunJuly: average high 94 °F, low 69 °F 94°69° JulAugust: average high 94 °F, low 70 °F 94°70° AugSeptember: average high 88 °F, low 66 °F 88°66° SepOctober: average high 78 °F, low 57 °F 78°57° OctNovember: average high 67 °F, low 47 °F 67°47° NovDecember: average high 59 °F, low 40 °F 59°40° Dec

Precipitation by month inches

0″1″2″3″January: 2.72 in precipitation 2.7 JanFebruary: 2.90 in precipitation 2.9 FebMarch: 0.90 in precipitation 0.9 MarApril: 0.22 in precipitation 0.2 AprMay: 0.07 in precipitation 0.1 MayJune: 0.02 in precipitation 0.0 JunJuly: 0.19 in precipitation 0.2 JulAugust: 0.22 in precipitation 0.2 AugSeptember: 0.17 in precipitation 0.2 SepOctober: 0.17 in precipitation 0.2 OctNovember: 0.31 in precipitation 0.3 NovDecember: 1.48 in precipitation 1.5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Morongo Valley N, CA (3 mi away); precipitation: Morongo Valley N, CA (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

6 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

922689a
Pioneertown, CA · 7 mi
922829b
Whitewater, CA · 8 mi
9224010a
Desert Hot Springs, CA · 10 mi
9225810a
North Palm Springs, CA · 11 mi
923397b
Forest Falls, CA · 13 mi
922849a
Yucca Valley, CA · 13 mi
922309b
Cabazon, CA · 14 mi
9226210a
Palm Springs, CA · 15 mi

California planting zones →

Questions about 92256

What planting zone is ZIP code 92256?

ZIP code 92256 (Morongo Valley, CA) is in USDA hardiness zone 9b on the 2023 map: the coldest night of an average winter reaches 25 to 30 °F (−3.9 to −1.1 °C).

When is the last frost in Morongo Valley, CA?

The median last spring frost (32 °F) near 92256 is February 25; after April 3 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Morongo Valley N station.

When is the first frost in Morongo Valley, CA?

The median first fall frost near 92256 is December 15, giving a median frost-free growing season of 297 days.

When should I plant tomatoes in 92256?

Start tomato seeds indoors around Dec 31 – Jan 14 and set transplants outside around Mar 4 – Mar 18, one to three weeks after the median last frost.

How much rain and snow does 92256 get?

About 9.4 inches of precipitation a year (NOAA 1991–2020 normals, Morongo Valley N station).

How hot do summers get in Morongo Valley, CA?

The average high peaks at 94 °F in July, with about 91 days a year at 90 °F or more.

What kind of soil does 92256 have?

The USDA soil survey maps Typic Haplargids at the center of ZIP 92256: cobbly fine sandy loam, well drained, pH about 7.5 (slightly alkaline).

Did spring come early in Morongo Valley, CA in 2026?

Spring leaf-out near 92256 came on Jan 24 in 2026, 13 days earlier than the 1991–2020 average (Feb 6), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Morongo Valley, CA?

Intermediate onions: the longest day near 92256 is 14 h 26 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 92256 change?

Yes. The 2012 USDA map put 92256 in zone 9a; the 2023 map puts it in zone 9b. The newer map uses 1991–2020 data and more weather stations.