Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for Barstow, CA

Barstow, CA is in USDA zone 9a across its 2 ZIP codes. The median last spring frost is February 22 and the first fall frost November 23.

Barstow on the zone map

Outlined: its 1 ZIP code areas · 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.

Zone9a20 to 25 °F

ZIP codes2

Last frostFeb 22

First frostNov 23

Growing season271 days

9a 2 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Barstow, 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 Barstow, CA

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostFebruary 22median — 50% chance of a later frost

Safe for tender plantsMarch 24only 10% chance of frost after

First fall frostNovember 23median — 10% chance by Nov 9

Growing season271 daysfrost-free, median

A hard freeze (28 °F) usually ends around January 30 and returns around December 6.

From the NOAA station Barstow, CA, elevation 2,221 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 Barstow

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Jan 11 – Jan 25

SpinachSow outdoors · Jan 11 – Feb 1

Broccoli, cabbageStart indoors · Dec 14 – Dec 28

Broccoli, cabbageTransplant · Feb 1 – Feb 15

Onion setsPlant outdoors · Jan 25 – Feb 8

PotatoesPlant outdoors · Feb 1 – Feb 15

LettuceSow outdoors · Jan 25 – Feb 8

Carrots, beetsSow outdoors · Feb 1 – Feb 15

TomatoesStart indoors · Dec 28 – Jan 11

TomatoesTransplant · Mar 1 – Mar 15

Peppers, eggplantStart indoors · Dec 14 – Dec 28

Peppers, eggplantTransplant · Mar 8 – Mar 22

BeansSow outdoors · Mar 1 – Mar 15

Sweet cornSow outdoors · Mar 1 – Mar 15

Cucumbers, squashSow outdoors · Mar 1 – Mar 15

Fall lettuce, spinachSow outdoors · Sep 28 – Oct 12

GarlicPlant cloves · Nov 9 – Dec 14

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 22) and first fall frost (Nov 23) 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 92311 came on Jan 27 — 3 days earlier than the 1991–2020 average (Jan 30).

average
Jan 302026
Jan 27

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 Barstow, CA

The soil mapped at the center of ZIP 92311 is Lithic Torriorthents — very gravelly fine sandy loam, somewhat excessively drained.

TextureVery gravelly fine sandy loamdrains and warms fast; dries out and needs more feeding

pH7.8slightly alkaline; most vegetables like 6.0–7.0

DrainageSomewhat excessively drainednatural drainage class

Organic matter0.3%low — add compost

Hydrologic groupDwater soaks in very slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Lithic Torriorthents, Typic Haplocalcids, and Rock outcrop; hyperthermic 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 92311; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Barstow, CA

Summer high102 °Faverage high, July

Winter low35 °Faverage low, January

Hot days133days a year at 90 °F or more

Freezing nights32nights a year at 32 °F or less

Growing degree days6,141base 50 °F — the season’s usable heat

Longest day14 h 30 mindaylight on June 21

Shortest day9 h 48 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation5 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Barstow, CA (5 mi away); precipitation: Barstow, CA (5 mi away). Daylight is calculated from latitude.

ZIP codes in Barstow

California planting zones →

Questions about Barstow

What planting zone is Barstow, CA?

Barstow, CA is in USDA hardiness zone 9a on the 2023 map (9a: 20 to 25 °F).

When is the last frost in Barstow, CA?

The median last spring frost is February 22 and the median first fall frost is November 23 (NOAA 1991–2020 normals, Barstow station).

When can I plant a garden in Barstow, CA?

Cool-season crops like peas and spinach go in around Jan 11 – Feb 1; tomatoes, peppers, beans and squash after about Mar 1, once frost risk has passed.

What kind of onions grow in Barstow, CA?

Intermediate onions: the longest day is 14 h 30 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

How much rain and snow does Barstow, CA get?

About 5 inches of precipitation a year (NOAA 1991–2020 normals).