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

Planting zone for 92342 — Helendale, CA

ZIP code 92342 (Helendale, San Bernardino County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is March 18 and the first fall frost November 11.

Where ZIP 92342 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.

Zone8b15 to 20 °F
Coldest night−9.4 to −6.7 °C
Last frostMar 18
First frostNov 11
2012 zone8b

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 8b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Helendale, 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 Helendale, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMarch 18median — 50% chance of a later frost
Safe for tender plantsApril 12only 10% chance of frost after
First fall frostNovember 11median — 10% chance by Oct 27
Growing season233 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 22 and returns around November 24.

From the NOAA station Victorville, CA — 16 miles away, elevation 2,881 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 92342

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 4 – Feb 18
SpinachSow outdoors · Feb 4 – Feb 25
Broccoli, cabbageStart indoors · Jan 7 – Jan 21
Broccoli, cabbageTransplant · Feb 25 – Mar 11
Onion setsPlant outdoors · Feb 18 – Mar 4
PotatoesPlant outdoors · Feb 25 – Mar 11
LettuceSow outdoors · Feb 18 – Mar 4
Carrots, beetsSow outdoors · Feb 25 – Mar 11
TomatoesStart indoors · Jan 21 – Feb 4
TomatoesTransplant · Mar 25 – Apr 8
Peppers, eggplantStart indoors · Jan 7 – Jan 21
Peppers, eggplantTransplant · Apr 1 – Apr 15
BeansSow outdoors · Mar 25 – Apr 8
Sweet cornSow outdoors · Mar 25 – Apr 8
Cucumbers, squashSow outdoors · Mar 25 – Apr 8
Fall lettuce, spinachSow outdoors · Sep 16 – Sep 30
GarlicPlant cloves · Oct 28 – Dec 2
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 18) and first fall frost (Nov 11) 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 92342 came on Jan 31 — about the same time as the 1991–2020 average (Feb 2).

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 Helendale, CA

The soil mapped at the center of ZIP 92342 is Torriorthents, well drained.

DrainageWell drainednatural drainage class
Farmland classNot prime farmlandUSDA classification

Map unit: TORRIORTHENTS-TORRIPSAMMENTS-URBAN LAND COMPLEX, 0 TO 9 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 92342; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Helendale, CA

Summer high98 °Faverage high, July
Winter low33 °Faverage low, January
Hot days119days a year at 90 °F or more
Freezing nights54nights a year at 32 °F or less
Growing degree days4,932base 50 °F — the season’s usable heat
Longest day14 h 29 mindaylight on June 21
Shortest day9 h 49 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation5.6 inper year, rain and melted snow

Average high and low, by month

20°30°40°50°60°70°80°90°100°110°32 °FJanuary: average high 58 °F, low 33 °F 58°33° JanFebruary: average high 61 °F, low 36 °F 61°36° FebMarch: average high 67 °F, low 40 °F 67°40° MarApril: average high 73 °F, low 44 °F 73°44° AprMay: average high 81 °F, low 51 °F 81°51° MayJune: average high 91 °F, low 58 °F 91°58° JunJuly: average high 98 °F, low 64 °F 98°64° JulAugust: average high 97 °F, low 63 °F 97°63° AugSeptember: average high 91 °F, low 58 °F 91°58° SepOctober: average high 79 °F, low 47 °F 79°47° OctNovember: average high 67 °F, low 38 °F 67°38° NovDecember: average high 57 °F, low 33 °F 57°33° Dec

Precipitation by month inches

0″1″2″January: 0.97 in precipitation 1.0 JanFebruary: 1.27 in precipitation 1.3 FebMarch: 0.78 in precipitation 0.8 MarApril: 0.33 in precipitation 0.3 AprMay: 0.09 in precipitation 0.1 MayJune: 0.04 in precipitation 0.0 JunJuly: 0.22 in precipitation 0.2 JulAugust: 0.11 in precipitation 0.1 AugSeptember: 0.16 in precipitation 0.2 SepOctober: 0.31 in precipitation 0.3 OctNovember: 0.35 in precipitation 0.3 NovDecember: 0.94 in precipitation 0.9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Victorville, CA (16 mi away); precipitation: Victorville, CA (16 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

923688b
Oro Grande, CA · 7 mi
923018b
Adelanto, CA · 13 mi
923948b
Victorville, CA · 14 mi
923479a
Hinkley, CA · 14 mi
923938b
Victorville, CA · 16 mi
923078b
Apple Valley, CA · 17 mi
923958b
Victorville, CA · 18 mi
923129a
Barstow, CA · 20 mi

California planting zones →

Questions about 92342

What planting zone is ZIP code 92342?

ZIP code 92342 (Helendale, 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 Helendale, CA?

The median last spring frost (32 °F) near 92342 is March 18; after April 12 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Victorville station.

When is the first frost in Helendale, CA?

The median first fall frost near 92342 is November 11, giving a median frost-free growing season of 233 days.

When should I plant tomatoes in 92342?

Start tomato seeds indoors around Jan 21 – Feb 4 and set transplants outside around Mar 25 – Apr 8, one to three weeks after the median last frost.

How much rain and snow does 92342 get?

About 5.6 inches of precipitation a year (NOAA 1991–2020 normals, Victorville station).

How hot do summers get in Helendale, CA?

The average high peaks at 98 °F in July, with about 119 days a year at 90 °F or more.

Did spring come early in Helendale, CA in 2026?

Spring leaf-out near 92342 came on Jan 31 in 2026, about the same as the 1991–2020 average (Feb 2), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Helendale, CA?

Intermediate onions: the longest day near 92342 is 14 h 29 min, so day-neutral types bulb best; long-day varieties may not bulb fully.