Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 30, 2026

Planting zone for Modesto, CA

Modesto, CA is in USDA zone 9b across its 10 ZIP codes. The median last spring frost is January 31 and the first fall frost December 5.

Modesto on the zone map

Outlined: its 7 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.

Zone9b25 to 30 °F

ZIP codes10

Last frostJan 31

First frostDec 5

Growing season312 days

9b 10 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

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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 Modesto, CA

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostJanuary 31median — 50% chance of a later frost

Safe for tender plantsFebruary 25only 10% chance of frost after

First fall frostDecember 5median — 10% chance by Nov 20

Growing season312 daysfrost-free, median

A hard freeze (28 °F) usually ends around January 8 and returns around December 21.

From the NOAA station Modesto City Co. Airport, CA, elevation 72 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 Modesto

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Dec 20 – Jan 3

SpinachSow outdoors · Dec 20 – Jan 10

Broccoli, cabbageStart indoors · Nov 22 – Dec 6

Broccoli, cabbageTransplant · Jan 10 – Jan 24

Onion setsPlant outdoors · Jan 3 – Jan 17

PotatoesPlant outdoors · Jan 10 – Jan 24

LettuceSow outdoors · Jan 3 – Jan 17

Carrots, beetsSow outdoors · Jan 10 – Jan 24

TomatoesStart indoors · Dec 6 – Dec 20

TomatoesTransplant · Feb 7 – Feb 21

Peppers, eggplantStart indoors · Nov 22 – Dec 6

Peppers, eggplantTransplant · Feb 14 – Feb 28

BeansSow outdoors · Feb 7 – Feb 21

Sweet cornSow outdoors · Feb 7 – Feb 21

Cucumbers, squashSow outdoors · Feb 7 – Feb 21

Fall lettuce, spinachSow outdoors · Oct 10 – Oct 24

GarlicPlant cloves · Nov 21 – Dec 26

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jan 31) and first fall frost (Dec 5) 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 95353 came on Jan 30 — about the same time as the 1991–2020 average (Jan 31).

average
Jan 312026
Jan 30

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 Modesto, CA

The soil mapped at the center of ZIP 95353 is Dinuba — fine sandy loam, moderately well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding

pH7.2neutral; most vegetables like 6.0–7.0

DrainageModerately well drainednatural drainage class

Organic matter0.75%low — add compost

Hydrologic groupCwater soaks in slowly

Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Dinuba fine sandy loam, 0 to 1 percent slopes, MLRA 17.

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 95353; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Modesto, CA

Summer high95 °Faverage high, July

Winter low39 °Faverage low, January

Hot days90days a year at 90 °F or more

Freezing nights12nights a year at 32 °F or less

Growing degree days5,078base 50 °F — the season’s usable heat

Longest day14 h 46 mindaylight on June 21

Shortest day9 h 33 mindaylight on December 21

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

Precipitation12.3 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: Modesto City Co. Airport, CA (3 mi away); precipitation: Modesto City Co. Airport, CA (3 mi away). Daylight is calculated from latitude.

ZIP codes in Modesto

California planting zones →

Questions about Modesto

What planting zone is Modesto, CA?

Modesto, CA is in USDA hardiness zone 9b on the 2023 map (9b: 25 to 30 °F).

When is the last frost in Modesto, CA?

The median last spring frost is January 31 and the median first fall frost is December 5 (NOAA 1991–2020 normals, Modesto City Co. Airport station).

When can I plant a garden in Modesto, CA?

Cool-season crops like peas and spinach go in around Dec 20 – Jan 10; tomatoes, peppers, beans and squash after about Feb 7, once frost risk has passed.

What kind of onions grow in Modesto, CA?

Intermediate onions: the longest day is 14 h 46 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

How much rain and snow does Modesto, CA get?

About 12.3 inches of precipitation a year (NOAA 1991–2020 normals).