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

Planting zone for 96122 — Portola, CA

ZIP code 96122 (Portola, Plumas County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is June 11 and the first fall frost September 10.

Where ZIP 96122 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 frostJun 11
First frostSep 10
2012 zone6b

Same zone as on the 2012 map. 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 Portola, 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 Portola, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostJune 11median — 50% chance of a later frost
Safe for tender plantsJuly 2only 10% chance of frost after
First fall frostSeptember 10median — 10% chance by Aug 22
Growing season91 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 17 and returns around October 1.

From the NOAA station Portola, CA — within 1 mile, elevation 4,849 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 96122

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 30 – May 14
SpinachSow outdoors · Apr 30 – May 21
Broccoli, cabbageStart indoors · Apr 2 – Apr 16
Broccoli, cabbageTransplant · May 21 – Jun 4
Onion setsPlant outdoors · May 14 – May 28
PotatoesPlant outdoors · May 21 – Jun 4
LettuceSow outdoors · May 14 – May 28
Carrots, beetsSow outdoors · May 21 – Jun 4
TomatoesStart indoors · Apr 16 – Apr 30
TomatoesTransplant · Jun 18 – Jul 2
Peppers, eggplantStart indoors · Apr 2 – Apr 16
Peppers, eggplantTransplant · Jun 25 – Jul 9
BeansSow outdoors · Jun 18 – Jul 2
Sweet cornSow outdoors · Jun 18 – Jul 2
Cucumbers, squashSow outdoors · Jun 18 – Jul 2
Fall lettuce, spinachSow outdoors · Jul 16 – Jul 30
GarlicPlant cloves · Aug 27 – Oct 1
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jun 11) and first fall frost (Sep 10) 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 96122 came on Mar 17 — 19 days earlier than the 1991–2020 average (Apr 5).

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 Portola, CA

The soil mapped at the center of ZIP 96122 is Chaix family — sandy loam, well drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding
pH6.8neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter4%moderate
Hydrologic groupAwater soaks in fast
Farmland classNot prime farmlandUSDA classification

Map unit: Chaix-Wapi families complex, 2 to 30 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 96122; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Portola, CA

Summer high86 °Faverage high, July
Winter low19 °Faverage low, January
Hot days22days a year at 90 °F or more
Freezing nights205nights a year at 32 °F or less
Growing degree days1,616base 50 °F — the season’s usable heat
Longest day15 h 00 mindaylight on June 21
Shortest day9 h 21 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation23.3 inper year, rain and melted snow
Snowfall38 inper year; 29 days with snow on the ground

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 43 °F, low 19 °F 43°19° JanFebruary: average high 46 °F, low 21 °F 46°21° FebMarch: average high 52 °F, low 25 °F 52°25° MarApril: average high 58 °F, low 29 °F 58°29° AprMay: average high 67 °F, low 35 °F 67°35° MayJune: average high 77 °F, low 40 °F 77°40° JunJuly: average high 86 °F, low 45 °F 86°45° JulAugust: average high 85 °F, low 43 °F 85°43° AugSeptember: average high 79 °F, low 37 °F 79°37° SepOctober: average high 66 °F, low 30 °F 66°30° OctNovember: average high 53 °F, low 24 °F 53°24° NovDecember: average high 42 °F, low 19 °F 42°19° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 4.16 in precipitation, 11.7 in snowfall 4.2❄12 JanFebruary: 3.93 in precipitation, 7.6 in snowfall 3.9❄8 FebMarch: 3.57 in precipitation, 6.4 in snowfall 3.6❄6 MarApril: 1.55 in precipitation, 1.8 in snowfall 1.6❄2 AprMay: 1.15 in precipitation, 0.2 in snowfall 1.1 MayJune: 0.52 in precipitation 0.5 JunJuly: 0.34 in precipitation 0.3 JulAugust: 0.30 in precipitation 0.3 AugSeptember: 0.44 in precipitation, 0.1 in snowfall 0.4 SepOctober: 1.07 in precipitation, 0.4 in snowfall 1.1 OctNovember: 2.03 in precipitation, 2.4 in snowfall 2.0❄2 NovDecember: 4.28 in precipitation, 7.2 in snowfall 4.3❄7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Portola, CA (within 1 mile); precipitation: Portola, CA (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

961296b
Beckwourth, CA · 6 mi
961067a
Clio, CA · 7 mi
961037a
Blairsden Graeagle, CA · 11 mi
961246b
Calpine, CA · 13 mi
961356b
Vinton, CA · 14 mi
961257a
Sierra City, CA · 16 mi
961186b
Loyalton, CA · 17 mi
961266b
Sierraville, CA · 19 mi

California planting zones →

Questions about 96122

What planting zone is ZIP code 96122?

ZIP code 96122 (Portola, 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 Portola, CA?

The median last spring frost (32 °F) near 96122 is June 11; after July 2 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Portola station.

When is the first frost in Portola, CA?

The median first fall frost near 96122 is September 10, giving a median frost-free growing season of 91 days.

When should I plant tomatoes in 96122?

Start tomato seeds indoors around Apr 16 – Apr 30 and set transplants outside around Jun 18 – Jul 2, one to three weeks after the median last frost.

How much rain and snow does 96122 get?

About 23.3 inches of precipitation a year and 38 inches of snowfall (NOAA 1991–2020 normals, Portola station).

How hot do summers get in Portola, CA?

The average high peaks at 86 °F in July, with about 22 days a year at 90 °F or more.

What kind of soil does 96122 have?

The USDA soil survey maps Chaix family at the center of ZIP 96122: sandy loam, well drained, pH about 6.8 (neutral).

Did spring come early in Portola, CA in 2026?

Spring leaf-out near 96122 came on Mar 17 in 2026, 19 days earlier than the 1991–2020 average (Apr 5), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Portola, CA?

Intermediate onions: the longest day near 96122 is 15 h 00 min, so day-neutral types bulb best; long-day varieties may not bulb fully.