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

Planting zone for 94566 — Pleasanton, CA

ZIP code 94566 (Pleasanton, Alameda County) is in USDA zone 9b: the coldest winter night averages 25 to 30 °F. The median last spring frost is February 15 and the first fall frost December 2.

Where ZIP 94566 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 15
First frostDec 2
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 Pleasanton, 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 Pleasanton, CA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostFebruary 15median — 50% chance of a later frost
Safe for tender plantsMarch 13only 10% chance of frost after
First fall frostDecember 2median — 10% chance by Nov 16
Growing season292 daysfrost-free, median

A hard freeze (28 °F) usually ends around January 10 and returns around December 18.

From the NOAA station Livermore, CA — 4 miles away, elevation 394 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 94566

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Jan 4 – Jan 18
SpinachSow outdoors · Jan 4 – Jan 25
Broccoli, cabbageStart indoors · Dec 7 – Dec 21
Broccoli, cabbageTransplant · Jan 25 – Feb 8
Onion setsPlant outdoors · Jan 18 – Feb 1
PotatoesPlant outdoors · Jan 25 – Feb 8
LettuceSow outdoors · Jan 18 – Feb 1
Carrots, beetsSow outdoors · Jan 25 – Feb 8
TomatoesStart indoors · Dec 21 – Jan 4
TomatoesTransplant · Feb 22 – Mar 8
Peppers, eggplantStart indoors · Dec 7 – Dec 21
Peppers, eggplantTransplant · Mar 1 – Mar 15
BeansSow outdoors · Feb 22 – Mar 8
Sweet cornSow outdoors · Feb 22 – Mar 8
Cucumbers, squashSow outdoors · Feb 22 – Mar 8
Fall lettuce, spinachSow outdoors · Oct 7 – Oct 21
GarlicPlant cloves · Nov 18 – Dec 23
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 15) and first fall frost (Dec 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 94566 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 Pleasanton, CA

The soil mapped at the center of ZIP 94566 is Perkins — loam, somewhat excessively drained.

TextureLoama good balance for most vegetables
pH5.8moderately acidic; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter1.5%low — add compost
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Perkins loam, 45 to 75 percent slopes, eroded.

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 94566; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Pleasanton, CA

Summer high89 °Faverage high, July
Winter low39 °Faverage low, January
Hot days57days a year at 90 °F or more
Freezing nights13nights a year at 32 °F or less
Growing degree days4,091base 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
Precipitation19.4 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°100°32 °FJanuary: average high 57 °F, low 39 °F 57°39° JanFebruary: average high 61 °F, low 41 °F 61°41° FebMarch: average high 66 °F, low 43 °F 66°43° MarApril: average high 71 °F, low 46 °F 71°46° AprMay: average high 77 °F, low 50 °F 77°50° MayJune: average high 84 °F, low 54 °F 84°54° JunJuly: average high 89 °F, low 57 °F 89°57° JulAugust: average high 89 °F, low 57 °F 89°57° AugSeptember: average high 86 °F, low 55 °F 86°55° SepOctober: average high 77 °F, low 50 °F 77°50° OctNovember: average high 65 °F, low 43 °F 65°43° NovDecember: average high 57 °F, low 39 °F 57°39° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 4.05 in precipitation 4.0 JanFebruary: 3.59 in precipitation 3.6 FebMarch: 2.96 in precipitation 3.0 MarApril: 1.30 in precipitation 1.3 AprMay: 0.63 in precipitation 0.6 MayJune: 0.16 in precipitation 0.2 JunJuly: 0.00 in precipitation 0.0 JulAugust: 0.04 in precipitation 0.0 AugSeptember: 0.08 in precipitation 0.1 SepOctober: 0.92 in precipitation 0.9 OctNovember: 2.20 in precipitation 2.2 NovDecember: 3.47 in precipitation 3.5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Livermore, CA (4 mi away); precipitation: Pleasanton 1.8 Sse, CA (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

945379b
Fremont, CA · 5 mi
9454010a
Hayward, CA · 5 mi
9455710a
Hayward, CA · 5 mi
945689b
Dublin, CA · 5 mi
945869b
Sunol, CA · 6 mi
945829b
San Ramon, CA · 9 mi
945519b
Livermore, CA · 9 mi
945369b
Fremont, CA · 9 mi

All 2 ZIP codes in Pleasanton → · California planting zones →

Questions about 94566

What planting zone is ZIP code 94566?

ZIP code 94566 (Pleasanton, 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 Pleasanton, CA?

The median last spring frost (32 °F) near 94566 is February 15; after March 13 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Livermore station.

When is the first frost in Pleasanton, CA?

The median first fall frost near 94566 is December 2, giving a median frost-free growing season of 292 days.

When should I plant tomatoes in 94566?

Start tomato seeds indoors around Dec 21 – Jan 4 and set transplants outside around Feb 22 – Mar 8, one to three weeks after the median last frost.

How much rain and snow does 94566 get?

About 19.4 inches of precipitation a year (NOAA 1991–2020 normals, Pleasanton 1.8 Sse station).

How hot do summers get in Pleasanton, CA?

The average high peaks at 89 °F in July, with about 57 days a year at 90 °F or more.

What kind of soil does 94566 have?

The USDA soil survey maps Perkins at the center of ZIP 94566: loam, somewhat excessively drained, pH about 5.8 (moderately acidic).

Did spring come early in Pleasanton, CA in 2026?

Spring leaf-out near 94566 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 Pleasanton, CA?

Intermediate onions: the longest day near 94566 is 14 h 46 min, so day-neutral types bulb best; long-day varieties may not bulb fully.