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

Planting zone for 95977 — Smartsville, CA

ZIP code 95977 (Smartsville, Nevada County) is in USDA zone 9b: the coldest winter night averages 25 to 30 °F. The median last spring frost is April 10 and the first fall frost November 13.

Where ZIP 95977 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.

Zone9b25 to 30 °F
Coldest night−3.9 to −1.1 °C
Last frostApr 10
First frostNov 13
2012 zone9b

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 9b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Smartsville, 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 Smartsville, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 10median — 50% chance of a later frost
Safe for tender plantsApril 30only 10% chance of frost after
First fall frostNovember 13median — 10% chance by Oct 26
Growing season215 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 9 and returns around December 1.

From the NOAA station Grass Valley #2, CA — 12 miles away, elevation 2,402 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 95977

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 27 – Mar 13
SpinachSow outdoors · Feb 27 – Mar 20
Broccoli, cabbageStart indoors · Jan 30 – Feb 13
Broccoli, cabbageTransplant · Mar 20 – Apr 3
Onion setsPlant outdoors · Mar 13 – Mar 27
PotatoesPlant outdoors · Mar 20 – Apr 3
LettuceSow outdoors · Mar 13 – Mar 27
Carrots, beetsSow outdoors · Mar 20 – Apr 3
TomatoesStart indoors · Feb 13 – Feb 27
TomatoesTransplant · Apr 17 – May 1
Peppers, eggplantStart indoors · Jan 30 – Feb 13
Peppers, eggplantTransplant · Apr 24 – May 8
BeansSow outdoors · Apr 17 – May 1
Sweet cornSow outdoors · Apr 17 – May 1
Cucumbers, squashSow outdoors · Apr 17 – May 1
Fall lettuce, spinachSow outdoors · Sep 18 – Oct 2
GarlicPlant cloves · Oct 30 – Dec 4
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 10) and first fall frost (Nov 13) 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 95977 came on Jan 30 — about the same time as the 1991–2020 average (Feb 1).

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 Smartsville, CA

The soil mapped at the center of ZIP 95977 is Sobrante — loam, well drained.

TextureLoama good balance for most vegetables
pH6.1slightly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2%moderate
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Sobrante-Auburn complex, 8 to 15 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 95977; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Smartsville, CA

Summer high88 °Faverage high, July
Winter low33 °Faverage low, January
Hot days36days a year at 90 °F or more
Freezing nights61nights a year at 32 °F or less
Growing degree days3,206base 50 °F — the season’s usable heat
Longest day14 h 56 mindaylight on June 21
Shortest day9 h 24 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation34.8 inper year, rain and melted snow

Average high and low, by month

20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 54 °F, low 33 °F 54°33° JanFebruary: average high 55 °F, low 34 °F 55°34° FebMarch: average high 58 °F, low 37 °F 58°37° MarApril: average high 63 °F, low 40 °F 63°40° AprMay: average high 71 °F, low 47 °F 71°47° MayJune: average high 80 °F, low 53 °F 80°53° JunJuly: average high 88 °F, low 58 °F 88°58° JulAugust: average high 87 °F, low 57 °F 87°57° AugSeptember: average high 82 °F, low 52 °F 82°52° SepOctober: average high 72 °F, low 44 °F 72°44° OctNovember: average high 60 °F, low 37 °F 60°37° NovDecember: average high 53 °F, low 33 °F 53°33° Dec

Precipitation by month inches

0″2″4″6″January: 5.95 in precipitation 6.0 JanFebruary: 6.10 in precipitation 6.1 FebMarch: 5.46 in precipitation 5.5 MarApril: 2.70 in precipitation 2.7 AprMay: 1.50 in precipitation 1.5 MayJune: 0.52 in precipitation 0.5 JunJuly: 0.00 in precipitation 0.0 JulAugust: 0.08 in precipitation 0.1 AugSeptember: 0.24 in precipitation 0.2 SepOctober: 1.78 in precipitation 1.8 OctNovember: 3.68 in precipitation 3.7 NovDecember: 6.78 in precipitation 6.8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Grass Valley #2, CA (12 mi away); precipitation: Harry L Englebright Dam, CA (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

959469b
Penn Valley, CA · 5 mi
959039b
Beale Afb, CA · 6 mi
959759a
Rough And Ready, CA · 8 mi
959189b
Browns Valley, CA · 9 mi
959499b
Grass Valley, CA · 10 mi
959629b
Oregon House, CA · 10 mi
956929b
Wheatland, CA · 11 mi
959019b
Marysville, CA · 11 mi

California planting zones →

Questions about 95977

What planting zone is ZIP code 95977?

ZIP code 95977 (Smartsville, 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 Smartsville, CA?

The median last spring frost (32 °F) near 95977 is April 10; after April 30 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Grass Valley #2 station.

When is the first frost in Smartsville, CA?

The median first fall frost near 95977 is November 13, giving a median frost-free growing season of 215 days.

When should I plant tomatoes in 95977?

Start tomato seeds indoors around Feb 13 – Feb 27 and set transplants outside around Apr 17 – May 1, one to three weeks after the median last frost.

How much rain and snow does 95977 get?

About 34.8 inches of precipitation a year (NOAA 1991–2020 normals, Harry L Englebright Dam station).

How hot do summers get in Smartsville, CA?

The average high peaks at 88 °F in July, with about 36 days a year at 90 °F or more.

What kind of soil does 95977 have?

The USDA soil survey maps Sobrante at the center of ZIP 95977: loam, well drained, pH about 6.1 (slightly acidic).

Did spring come early in Smartsville, CA in 2026?

Spring leaf-out near 95977 came on Jan 30 in 2026, about the same as the 1991–2020 average (Feb 1), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Smartsville, CA?

Intermediate onions: the longest day near 95977 is 14 h 56 min, so day-neutral types bulb best; long-day varieties may not bulb fully.