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

Planting zone for 95223 — Arnold, CA

ZIP code 95223 (Arnold, Calaveras County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is May 12 and the first fall frost October 6.

Where ZIP 95223 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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostMay 12
First frostOct 6
2012 zone8b

Was 8b on the 2012 map — 2 zones colder now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Arnold, 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 Arnold, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 12median — 50% chance of a later frost
Safe for tender plantsJune 7only 10% chance of frost after
First fall frostOctober 6median — 10% chance by Sep 20
Growing season145 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 24 and returns around October 18.

From the NOAA station Topaz Lake, NV — 25 miles away, elevation 5,292 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 95223

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 31 – Apr 14
SpinachSow outdoors · Mar 31 – Apr 21
Broccoli, cabbageStart indoors · Mar 3 – Mar 17
Broccoli, cabbageTransplant · Apr 21 – May 5
Onion setsPlant outdoors · Apr 14 – Apr 28
PotatoesPlant outdoors · Apr 21 – May 5
LettuceSow outdoors · Apr 14 – Apr 28
Carrots, beetsSow outdoors · Apr 21 – May 5
TomatoesStart indoors · Mar 17 – Mar 31
TomatoesTransplant · May 19 – Jun 2
Peppers, eggplantStart indoors · Mar 3 – Mar 17
Peppers, eggplantTransplant · May 26 – Jun 9
BeansSow outdoors · May 19 – Jun 2
Sweet cornSow outdoors · May 19 – Jun 2
Cucumbers, squashSow outdoors · May 19 – Jun 2
Fall lettuce, spinachSow outdoors · Aug 11 – Aug 25
GarlicPlant cloves · Sep 22 – Oct 27
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 12) and first fall frost (Oct 6) 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 95223 came on Apr 17 — 20 days earlier than the 1991–2020 average (May 7).

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 Arnold, CA

The soil mapped at the center of ZIP 95223 is Andic Cryumbrepts — sandy loam, somewhat excessively drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding
pH6.0slightly acidic; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter4%moderate
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Andic Cryumbrepts-Lithic Cryumbrepts-Rock outcrop compl ex, 20 to 70 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 95223; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Arnold, CA

Summer high92 °Faverage high, July
Winter low22 °Faverage low, January
Hot days57days a year at 90 °F or more
Freezing nights154nights a year at 32 °F or less
Growing degree days2,776base 50 °F — the season’s usable heat
Longest day14 h 51 mindaylight on June 21
Shortest day9 h 29 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation53.5 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 47 °F, low 22 °F 47°22° JanFebruary: average high 51 °F, low 25 °F 51°25° FebMarch: average high 58 °F, low 29 °F 58°29° MarApril: average high 63 °F, low 33 °F 63°33° AprMay: average high 72 °F, low 41 °F 72°41° MayJune: average high 82 °F, low 48 °F 82°48° JunJuly: average high 92 °F, low 55 °F 92°55° JulAugust: average high 90 °F, low 53 °F 90°53° AugSeptember: average high 82 °F, low 46 °F 82°46° SepOctober: average high 70 °F, low 36 °F 70°36° OctNovember: average high 56 °F, low 28 °F 56°28° NovDecember: average high 46 °F, low 22 °F 46°22° Dec

Precipitation by month inches

0″2″4″6″8″10″January: 9.30 in precipitation 9.3 JanFebruary: 8.29 in precipitation 8.3 FebMarch: 7.70 in precipitation 7.7 MarApril: 4.71 in precipitation 4.7 AprMay: 2.93 in precipitation 2.9 MayJune: 1.05 in precipitation 1.1 JunJuly: 0.59 in precipitation 0.6 JulAugust: 0.50 in precipitation 0.5 AugSeptember: 0.89 in precipitation 0.9 SepOctober: 3.08 in precipitation 3.1 OctNovember: 5.27 in precipitation 5.3 NovDecember: 9.21 in precipitation 9.2 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Topaz Lake, NV (25 mi away); precipitation: Ebbetts Pass, CA (7 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

961076b
Coleville, CA · 15 mi
953646b
Pinecrest, CA · 16 mi
956466b
Kirkwood, CA · 17 mi
953757b
Strawberry, CA · 17 mi
961337a
Topaz, CA · 21 mi
961206b
Markleeville, CA · 21 mi
956447a
Kit Carson, CA · 22 mi
953358a
Long Barn, CA · 27 mi

California planting zones →

Questions about 95223

What planting zone is ZIP code 95223?

ZIP code 95223 (Arnold, CA) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Arnold, CA?

The median last spring frost (32 °F) near 95223 is May 12; after June 7 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Topaz Lake station.

When is the first frost in Arnold, CA?

The median first fall frost near 95223 is October 6, giving a median frost-free growing season of 145 days.

When should I plant tomatoes in 95223?

Start tomato seeds indoors around Mar 17 – Mar 31 and set transplants outside around May 19 – Jun 2, one to three weeks after the median last frost.

How much rain and snow does 95223 get?

About 53.5 inches of precipitation a year (NOAA 1991–2020 normals, Ebbetts Pass station).

How hot do summers get in Arnold, CA?

The average high peaks at 92 °F in July, with about 57 days a year at 90 °F or more.

What kind of soil does 95223 have?

The USDA soil survey maps Andic Cryumbrepts at the center of ZIP 95223: sandy loam, somewhat excessively drained, pH about 6.0 (slightly acidic).

Did spring come early in Arnold, CA in 2026?

Spring leaf-out near 95223 came on Apr 17 in 2026, 20 days earlier than the 1991–2020 average (May 7), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Arnold, CA?

Intermediate onions: the longest day near 95223 is 14 h 51 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 95223 change?

Yes. The 2012 USDA map put 95223 in zone 8b; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.