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

Planting zone for 94573 — Rutherford, CA

ZIP code 94573 (Rutherford, Napa County) is in USDA zone 9b: the coldest winter night averages 25 to 30 °F. The median last spring frost is February 3 and the first fall frost December 4.

Where ZIP 94573 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 frostFeb 3
First frostDec 4
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 Rutherford, 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 Rutherford, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostFebruary 3median — 50% chance of a later frost
Safe for tender plantsMarch 13only 10% chance of frost after
First fall frostDecember 4median — 10% chance by Nov 14
Growing season306 daysfrost-free, median

A hard freeze (28 °F) usually ends around January 5 and returns around December 17.

From the NOAA station Saint Helena, CA — 4 miles away, elevation 226 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 94573

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Dec 23 – Jan 6
SpinachSow outdoors · Dec 23 – Jan 13
Broccoli, cabbageStart indoors · Nov 25 – Dec 9
Broccoli, cabbageTransplant · Jan 13 – Jan 27
Onion setsPlant outdoors · Jan 6 – Jan 20
PotatoesPlant outdoors · Jan 13 – Jan 27
LettuceSow outdoors · Jan 6 – Jan 20
Carrots, beetsSow outdoors · Jan 13 – Jan 27
TomatoesStart indoors · Dec 9 – Dec 23
TomatoesTransplant · Feb 10 – Feb 24
Peppers, eggplantStart indoors · Nov 25 – Dec 9
Peppers, eggplantTransplant · Feb 17 – Mar 3
BeansSow outdoors · Feb 10 – Feb 24
Sweet cornSow outdoors · Feb 10 – Feb 24
Cucumbers, squashSow outdoors · Feb 10 – Feb 24
Fall lettuce, spinachSow outdoors · Oct 9 – Oct 23
GarlicPlant cloves · Nov 20 – Dec 25
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 3) and first fall frost (Dec 4) 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 94573 came on Jan 28 — about the same time as the 1991–2020 average (Jan 30).

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 Rutherford, CA

The soil mapped at the center of ZIP 94573 is Bale — loam, somewhat poorly drained.

TextureLoama good balance for most vegetables
pH6.1slightly acidic; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter2%moderate
Hydrologic groupBwater soaks in moderately
Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Bale loam, 0 to 2 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 94573; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Rutherford, CA

Summer high89 °Faverage high, July
Winter low40 °Faverage low, January
Hot days55days a year at 90 °F or more
Freezing nights14nights a year at 32 °F or less
Growing degree days4,262base 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
Precipitation34 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°100°32 °FJanuary: average high 59 °F, low 40 °F 59°40° JanFebruary: average high 63 °F, low 42 °F 63°42° FebMarch: average high 67 °F, low 44 °F 67°44° MarApril: average high 72 °F, low 46 °F 72°46° AprMay: average high 78 °F, low 51 °F 78°51° MayJune: average high 85 °F, low 54 °F 85°54° JunJuly: average high 89 °F, low 56 °F 89°56° JulAugust: average high 89 °F, low 56 °F 89°56° AugSeptember: average high 87 °F, low 54 °F 87°54° SepOctober: average high 78 °F, low 49 °F 78°49° OctNovember: average high 66 °F, low 44 °F 66°44° NovDecember: average high 58 °F, low 40 °F 58°40° Dec

Precipitation by month inches

0″2″4″6″8″January: 6.47 in precipitation 6.5 JanFebruary: 6.71 in precipitation 6.7 FebMarch: 4.98 in precipitation 5.0 MarApril: 1.97 in precipitation 2.0 AprMay: 1.31 in precipitation 1.3 MayJune: 0.35 in precipitation 0.3 JunJuly: 0.01 in precipitation 0.0 JulAugust: 0.04 in precipitation 0.0 AugSeptember: 0.06 in precipitation 0.1 SepOctober: 1.65 in precipitation 1.6 OctNovember: 3.24 in precipitation 3.2 NovDecember: 7.18 in precipitation 7.2 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Saint Helena, CA (4 mi away); precipitation: Saint Helena, CA (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 9b.

945629b
Oakville, CA · 2 mi
945999b
Yountville, CA · 5 mi
945749b
Saint Helena, CA · 6 mi
954529b
Kenwood, CA · 6 mi
945769b
Deer Park, CA · 7 mi
954429b
Glen Ellen, CA · 7 mi
954099b
Santa Rosa, CA · 8 mi
945089b
Angwin, CA · 9 mi

California planting zones →

Questions about 94573

What planting zone is ZIP code 94573?

ZIP code 94573 (Rutherford, 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 Rutherford, CA?

The median last spring frost (32 °F) near 94573 is February 3; after March 13 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Saint Helena station.

When is the first frost in Rutherford, CA?

The median first fall frost near 94573 is December 4, giving a median frost-free growing season of 306 days.

When should I plant tomatoes in 94573?

Start tomato seeds indoors around Dec 9 – Dec 23 and set transplants outside around Feb 10 – Feb 24, one to three weeks after the median last frost.

How much rain and snow does 94573 get?

About 34 inches of precipitation a year (NOAA 1991–2020 normals, Saint Helena station).

How hot do summers get in Rutherford, CA?

The average high peaks at 89 °F in July, with about 55 days a year at 90 °F or more.

What kind of soil does 94573 have?

The USDA soil survey maps Bale at the center of ZIP 94573: loam, somewhat poorly drained, pH about 6.1 (slightly acidic).

Did spring come early in Rutherford, CA in 2026?

Spring leaf-out near 94573 came on Jan 28 in 2026, about the same as the 1991–2020 average (Jan 30), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Rutherford, CA?

Intermediate onions: the longest day near 94573 is 14 h 51 min, so day-neutral types bulb best; long-day varieties may not bulb fully.