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

Planting zone for 95311 — Coulterville, CA

ZIP code 95311 (Coulterville, Mariposa County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is April 22 and the first fall frost November 2.

Where ZIP 95311 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 22
First frostNov 2
2012 zone9a

Was 9a on the 2012 map — half a zone colder 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 Coulterville, 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 Coulterville, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 22median — 50% chance of a later frost
Safe for tender plantsMay 14only 10% chance of frost after
First fall frostNovember 2median — 10% chance by Oct 13
Growing season192 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 29 and returns around November 19.

From the NOAA station Groveland 2, CA — 12 miles away, elevation 2,799 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 95311

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 11 – Mar 25
SpinachSow outdoors · Mar 11 – Apr 1
Broccoli, cabbageStart indoors · Feb 11 – Feb 25
Broccoli, cabbageTransplant · Apr 1 – Apr 15
Onion setsPlant outdoors · Mar 25 – Apr 8
PotatoesPlant outdoors · Apr 1 – Apr 15
LettuceSow outdoors · Mar 25 – Apr 8
Carrots, beetsSow outdoors · Apr 1 – Apr 15
TomatoesStart indoors · Feb 25 – Mar 11
TomatoesTransplant · Apr 29 – May 13
Peppers, eggplantStart indoors · Feb 11 – Feb 25
Peppers, eggplantTransplant · May 6 – May 20
BeansSow outdoors · Apr 29 – May 13
Sweet cornSow outdoors · Apr 29 – May 13
Cucumbers, squashSow outdoors · Apr 29 – May 13
Fall lettuce, spinachSow outdoors · Sep 7 – Sep 21
GarlicPlant cloves · Oct 19 – Nov 23
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 22) and first fall frost (Nov 2) 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 95311 came on Jan 30 — 18 days earlier than the 1991–2020 average (Feb 17).

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 Coulterville, CA

The soil mapped at the center of ZIP 95311 is Josephine family — gravelly loam, well drained.

TextureGravelly loama good balance for most vegetables
pH6.0slightly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter4.5%moderate
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Josephine-Sites families complex, moderately deep, 15 t o 35 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 95311; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Coulterville, CA

Summer high91 °Faverage high, July
Winter low31 °Faverage low, January
Hot days59days a year at 90 °F or more
Freezing nights91nights a year at 32 °F or less
Growing degree days3,242base 50 °F — the season’s usable heat
Longest day14 h 46 mindaylight on June 21
Shortest day9 h 33 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation37.5 inper year, rain and melted snow
Snowfall8 inper year

Average high and low, by month

20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 53 °F, low 31 °F 53°31° JanFebruary: average high 55 °F, low 32 °F 55°32° FebMarch: average high 60 °F, low 35 °F 60°35° MarApril: average high 65 °F, low 38 °F 65°38° AprMay: average high 73 °F, low 44 °F 73°44° MayJune: average high 83 °F, low 51 °F 83°51° JunJuly: average high 91 °F, low 56 °F 91°56° JulAugust: average high 91 °F, low 55 °F 91°55° AugSeptember: average high 85 °F, low 50 °F 85°50° SepOctober: average high 74 °F, low 42 °F 74°42° OctNovember: average high 60 °F, low 35 °F 60°35° NovDecember: average high 52 °F, low 31 °F 52°31° Dec

Precipitation by month inches · ❄ = snowfall

0″2″4″6″8″January: 7.40 in precipitation, 1.8 in snowfall 7.4❄2 JanFebruary: 6.74 in precipitation, 1.6 in snowfall 6.7❄2 FebMarch: 5.83 in precipitation, 1.7 in snowfall 5.8❄2 MarApril: 3.05 in precipitation, 0.5 in snowfall 3.0❄1 AprMay: 1.52 in precipitation 1.5 MayJune: 0.53 in precipitation 0.5 JunJuly: 0.14 in precipitation 0.1 JulAugust: 0.01 in precipitation 0.0 AugSeptember: 0.22 in precipitation 0.2 SepOctober: 2.65 in precipitation 2.6 OctNovember: 3.09 in precipitation, 0.9 in snowfall 3.1❄1 NovDecember: 6.35 in precipitation, 1.7 in snowfall 6.3❄2 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Groveland 2, CA (12 mi away); precipitation: Groveland Rs, CA (8 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.

953459a
Midpines, CA · 11 mi
953479b
Moccasin, CA · 13 mi
953389a
Mariposa, CA · 15 mi
953188b
El Portal, CA · 16 mi
953059b
Big Oak Flat, CA · 17 mi
953259b
Hornitos, CA · 18 mi
953299b
La Grange, CA · 18 mi
953798b
Tuolumne, CA · 19 mi

California planting zones →

Questions about 95311

What planting zone is ZIP code 95311?

ZIP code 95311 (Coulterville, 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 Coulterville, CA?

The median last spring frost (32 °F) near 95311 is April 22; after May 14 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Groveland 2 station.

When is the first frost in Coulterville, CA?

The median first fall frost near 95311 is November 2, giving a median frost-free growing season of 192 days.

When should I plant tomatoes in 95311?

Start tomato seeds indoors around Feb 25 – Mar 11 and set transplants outside around Apr 29 – May 13, one to three weeks after the median last frost.

How much rain and snow does 95311 get?

About 37.5 inches of precipitation a year and 8 inches of snowfall (NOAA 1991–2020 normals, Groveland Rs station).

How hot do summers get in Coulterville, CA?

The average high peaks at 91 °F in July, with about 59 days a year at 90 °F or more.

What kind of soil does 95311 have?

The USDA soil survey maps Josephine family at the center of ZIP 95311: gravelly loam, well drained, pH about 6.0 (slightly acidic).

Did spring come early in Coulterville, CA in 2026?

Spring leaf-out near 95311 came on Jan 30 in 2026, 18 days earlier than the 1991–2020 average (Feb 17), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Coulterville, CA?

Intermediate onions: the longest day near 95311 is 14 h 46 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 95311 change?

Yes. The 2012 USDA map put 95311 in zone 9a; the 2023 map puts it in zone 8b. The newer map uses 1991–2020 data and more weather stations.