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

Planting zone for 95910 — Alleghany, CA

ZIP code 95910 (Alleghany, Sierra County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is April 28 and the first fall frost October 25.

Where ZIP 95910 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 frostApr 28
First frostOct 25
2012 zone8a

Was 8a 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 8b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Alleghany, 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 Alleghany, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 28median — 50% chance of a later frost
Safe for tender plantsMay 22only 10% chance of frost after
First fall frostOctober 25median — 10% chance by Oct 9
Growing season178 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 6 and returns around November 10.

From the NOAA station Downieville, CA — 7 miles away, elevation 2,917 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 95910

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 17 – Mar 31
SpinachSow outdoors · Mar 17 – Apr 7
Broccoli, cabbageStart indoors · Feb 17 – Mar 3
Broccoli, cabbageTransplant · Apr 7 – Apr 21
Onion setsPlant outdoors · Mar 31 – Apr 14
PotatoesPlant outdoors · Apr 7 – Apr 21
LettuceSow outdoors · Mar 31 – Apr 14
Carrots, beetsSow outdoors · Apr 7 – Apr 21
TomatoesStart indoors · Mar 3 – Mar 17
TomatoesTransplant · May 5 – May 19
Peppers, eggplantStart indoors · Feb 17 – Mar 3
Peppers, eggplantTransplant · May 12 – May 26
BeansSow outdoors · May 5 – May 19
Sweet cornSow outdoors · May 5 – May 19
Cucumbers, squashSow outdoors · May 5 – May 19
Fall lettuce, spinachSow outdoors · Aug 30 – Sep 13
GarlicPlant cloves · Oct 11 – Nov 15
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 28) and first fall frost (Oct 25) 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 95910 came on Feb 4 — 19 days earlier than the 1991–2020 average (Feb 23).

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 Alleghany, CA

The soil mapped at the center of ZIP 95910 is Jocal — loam, well drained.

TextureLoama good balance for most vegetables
pH6.1slightly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3.5%moderate
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Jocal-Jocal variant-Cryumbrepts, wet complex, 50 to 75 percent s lopes.

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 95910; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Alleghany, CA

Summer high89 °Faverage high, July
Winter low29 °Faverage low, December
Hot days53days a year at 90 °F or more
Freezing nights112nights a year at 32 °F or less
Growing degree days2,642base 50 °F — the season’s usable heat
Longest day14 h 57 mindaylight on June 21
Shortest day9 h 23 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation64.9 inper year, rain and melted snow
Snowfall26 inper year; 18 days with snow on the ground

Average high and low, by month

20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 48 °F, low 30 °F 48°30° JanFebruary: average high 52 °F, low 31 °F 52°31° FebMarch: average high 58 °F, low 33 °F 58°33° MarApril: average high 63 °F, low 36 °F 63°36° AprMay: average high 72 °F, low 42 °F 72°42° MayJune: average high 81 °F, low 46 °F 81°46° JunJuly: average high 89 °F, low 51 °F 89°51° JulAugust: average high 89 °F, low 50 °F 89°50° AugSeptember: average high 83 °F, low 46 °F 83°46° SepOctober: average high 72 °F, low 39 °F 72°39° OctNovember: average high 56 °F, low 33 °F 56°33° NovDecember: average high 46 °F, low 29 °F 46°29° Dec

Precipitation by month inches · ❄ = snowfall

0″2″4″6″8″10″12″January: 11.26 in precipitation, 6.4 in snowfall 11.3❄6 JanFebruary: 10.73 in precipitation, 7.9 in snowfall 10.7❄8 FebMarch: 10.00 in precipitation, 4.2 in snowfall 10.0❄4 MarApril: 5.34 in precipitation, 1.2 in snowfall 5.3❄1 AprMay: 3.65 in precipitation, 0.1 in snowfall 3.6 MayJune: 1.07 in precipitation 1.1 JunJuly: 0.06 in precipitation 0.1 JulAugust: 0.19 in precipitation 0.2 AugSeptember: 0.66 in precipitation 0.7 SepOctober: 3.34 in precipitation, 0.1 in snowfall 3.3 OctNovember: 6.81 in precipitation, 1.2 in snowfall 6.8❄1 NovDecember: 11.81 in precipitation, 5.1 in snowfall 11.8❄5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Downieville, CA (7 mi away); precipitation: Downieville, CA (7 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

959448b
Goodyears Bar, CA · 5 mi
959868b
Washington, CA · 8 mi
959599a
Nevada City, CA · 8 mi
959368a
Downieville, CA · 9 mi
959609a
North San Juan, CA · 10 mi
959229a
Camptonville, CA · 13 mi
961257a
Sierra City, CA · 16 mi
957158a
Emigrant Gap, CA · 16 mi

California planting zones →

Questions about 95910

What planting zone is ZIP code 95910?

ZIP code 95910 (Alleghany, 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 Alleghany, CA?

The median last spring frost (32 °F) near 95910 is April 28; after May 22 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Downieville station.

When is the first frost in Alleghany, CA?

The median first fall frost near 95910 is October 25, giving a median frost-free growing season of 178 days.

When should I plant tomatoes in 95910?

Start tomato seeds indoors around Mar 3 – Mar 17 and set transplants outside around May 5 – May 19, one to three weeks after the median last frost.

How much rain and snow does 95910 get?

About 64.9 inches of precipitation a year and 26 inches of snowfall (NOAA 1991–2020 normals, Downieville station).

How hot do summers get in Alleghany, CA?

The average high peaks at 89 °F in July, with about 53 days a year at 90 °F or more.

What kind of soil does 95910 have?

The USDA soil survey maps Jocal at the center of ZIP 95910: loam, well drained, pH about 6.1 (slightly acidic).

Did spring come early in Alleghany, CA in 2026?

Spring leaf-out near 95910 came on Feb 4 in 2026, 19 days earlier than the 1991–2020 average (Feb 23), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Alleghany, CA?

Intermediate onions: the longest day near 95910 is 14 h 57 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 95910 change?

Yes. The 2012 USDA map put 95910 in zone 8a; the 2023 map puts it in zone 8b. The newer map uses 1991–2020 data and more weather stations.