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

Planting zone for 95234 — Holt, CA

ZIP code 95234 (Holt, San Joaquin County) is in USDA zone 9b: the coldest winter night averages 25 to 30 °F. The median last spring frost is February 5 and the first fall frost December 8.

Where ZIP 95234 is

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 5
First frostDec 8
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 Holt, 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 Holt, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostFebruary 5median — 50% chance of a later frost
Safe for tender plantsMarch 11only 10% chance of frost after
First fall frostDecember 8median — 10% chance by Nov 17
Growing season305 daysfrost-free, median

A hard freeze (28 °F) usually ends around January 11 and returns around December 23.

From the NOAA station Stockton Fire Stn 4, CA — 7 miles away, elevation 13 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 95234

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Dec 25 – Jan 8
SpinachSow outdoors · Dec 25 – Jan 15
Broccoli, cabbageStart indoors · Nov 27 – Dec 11
Broccoli, cabbageTransplant · Jan 15 – Jan 29
Onion setsPlant outdoors · Jan 8 – Jan 22
PotatoesPlant outdoors · Jan 15 – Jan 29
LettuceSow outdoors · Jan 8 – Jan 22
Carrots, beetsSow outdoors · Jan 15 – Jan 29
TomatoesStart indoors · Dec 11 – Dec 25
TomatoesTransplant · Feb 12 – Feb 26
Peppers, eggplantStart indoors · Nov 27 – Dec 11
Peppers, eggplantTransplant · Feb 19 – Mar 5
BeansSow outdoors · Feb 12 – Feb 26
Sweet cornSow outdoors · Feb 12 – Feb 26
Cucumbers, squashSow outdoors · Feb 12 – Feb 26
Fall lettuce, spinachSow outdoors · Oct 13 – Oct 27
GarlicPlant cloves · Nov 24 – Dec 29
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 5) and first fall frost (Dec 8) 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 95234 came on Jan 31 — about the same time as the 1991–2020 average (Jan 31).

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 Holt, CA

The soil mapped at the center of ZIP 95234 is Peltier — mucky clay loam, poorly drained.

TextureMucky clay loamholds water and nutrients; slow to drain and warm up
pH6.5neutral; most vegetables like 6.0–7.0
DrainagePoorly drainedconsider raised beds
Organic matter17.5%high
Hydrologic groupCwater soaks in slowly
Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Peltier mucky clay loam, partially drained, 0 to 2 percent slopes, MLRA 16.

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 95234; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Holt, CA

Summer high95 °Faverage high, July
Winter low39 °Faverage low, January
Hot days90days a year at 90 °F or more
Freezing nights25nights a year at 32 °F or less
Growing degree days5,277base 50 °F — the season’s usable heat
Longest day14 h 48 mindaylight on June 21
Shortest day9 h 32 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation14.5 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°100°110°32 °FJanuary: average high 58 °F, low 39 °F 58°39° JanFebruary: average high 65 °F, low 42 °F 65°42° FebMarch: average high 70 °F, low 46 °F 70°46° MarApril: average high 75 °F, low 49 °F 75°49° AprMay: average high 83 °F, low 54 °F 83°54° MayJune: average high 91 °F, low 58 °F 91°58° JunJuly: average high 95 °F, low 61 °F 95°61° JulAugust: average high 95 °F, low 60 °F 95°60° AugSeptember: average high 92 °F, low 57 °F 92°57° SepOctober: average high 82 °F, low 51 °F 82°51° OctNovember: average high 69 °F, low 44 °F 69°44° NovDecember: average high 59 °F, low 39 °F 59°39° Dec

Precipitation by month inches

0″1″2″3″January: 2.94 in precipitation 2.9 JanFebruary: 2.46 in precipitation 2.5 FebMarch: 1.86 in precipitation 1.9 MarApril: 1.24 in precipitation 1.2 AprMay: 0.78 in precipitation 0.8 MayJune: 0.22 in precipitation 0.2 JunJuly: 0.00 in precipitation 0.0 JulAugust: 0.03 in precipitation 0.0 AugSeptember: 0.10 in precipitation 0.1 SepOctober: 0.86 in precipitation 0.9 OctNovember: 1.39 in precipitation 1.4 NovDecember: 2.60 in precipitation 2.6 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Stockton Fire Stn 4, CA (7 mi away); precipitation: Stockton 2.5 Ne, CA (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 9b.

952089b
Stockton, CA · <1 mi
952069b
Stockton, CA · 2 mi
952039b
Stockton, CA · 5 mi
952049b
Stockton, CA · 6 mi
952079b
Stockton, CA · 7 mi
952979b
Stockton, CA · 7 mi
952679b
Stockton, CA · 7 mi
952969b
Stockton, CA · 8 mi

California planting zones →

Questions about 95234

What planting zone is ZIP code 95234?

ZIP code 95234 (Holt, 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 Holt, CA?

The median last spring frost (32 °F) near 95234 is February 5; after March 11 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Stockton Fire Stn 4 station.

When is the first frost in Holt, CA?

The median first fall frost near 95234 is December 8, giving a median frost-free growing season of 305 days.

When should I plant tomatoes in 95234?

Start tomato seeds indoors around Dec 11 – Dec 25 and set transplants outside around Feb 12 – Feb 26, one to three weeks after the median last frost.

How much rain and snow does 95234 get?

About 14.5 inches of precipitation a year (NOAA 1991–2020 normals, Stockton 2.5 Ne station).

How hot do summers get in Holt, CA?

The average high peaks at 95 °F in July, with about 90 days a year at 90 °F or more.

What kind of soil does 95234 have?

The USDA soil survey maps Peltier at the center of ZIP 95234: mucky clay loam, poorly drained, pH about 6.5 (neutral).

Did spring come early in Holt, CA in 2026?

Spring leaf-out near 95234 came on Jan 31 in 2026, about the same as the 1991–2020 average (Jan 31), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Holt, CA?

Intermediate onions: the longest day near 95234 is 14 h 48 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 95234 change?

Yes. The 2012 USDA map put 95234 in zone 9a; the 2023 map puts it in zone 9b. The newer map uses 1991–2020 data and more weather stations.