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

Planting zone for 94525 — Crockett, CA

ZIP code 94525 (Crockett, Contra Costa County) is in USDA zone 9b: the coldest winter night averages 25 to 30 °F.

Where ZIP 94525 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 frostrare
First frostrare
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 Crockett, 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

A 32 °F frost doesn't happen here in most winters. At the nearest station (NOAA station Vallejo, CA — 4 miles away, elevation 341 ft) the median growing season is 346 days. When frost does come, it is a midwinter night or two; cover tender plants when a freeze is forecast.

Frost data: NOAA NCEI U.S. Climate Normals 1991–2020.

When spring arrived in 2026

In 2026, spring leaf-out near 94525 came on Jan 29 — about the same time as the 1991–2020 average (Jan 29).

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 Crockett, CA

The soil mapped at the center of ZIP 94525 is Sehorn — clay, well drained.

TextureClayholds water and nutrients; slow to drain and warm up
pH6.7neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2%moderate
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Sehorn clay, 30 to 50 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 94525; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Crockett, CA

Summer high86 °Faverage high, August
Winter low42 °Faverage low, January
Hot days36days a year at 90 °F or more
Freezing nights5nights a year at 32 °F or less
Growing degree days4,389base 50 °F — the season’s usable heat
Longest day14 h 49 mindaylight on June 21
Shortest day9 h 31 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation21.5 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 42 °F 57°42° JanFebruary: average high 63 °F, low 45 °F 63°45° FebMarch: average high 68 °F, low 46 °F 68°46° MarApril: average high 73 °F, low 47 °F 73°47° AprMay: average high 78 °F, low 51 °F 78°51° MayJune: average high 83 °F, low 54 °F 83°54° JunJuly: average high 85 °F, low 56 °F 85°56° JulAugust: average high 86 °F, low 56 °F 86°56° AugSeptember: average high 86 °F, low 57 °F 86°57° SepOctober: average high 79 °F, low 54 °F 79°54° OctNovember: average high 66 °F, low 47 °F 66°47° NovDecember: average high 58 °F, low 42 °F 58°42° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 4.46 in precipitation 4.5 JanFebruary: 3.58 in precipitation 3.6 FebMarch: 3.18 in precipitation 3.2 MarApril: 1.45 in precipitation 1.4 AprMay: 0.80 in precipitation 0.8 MayJune: 0.22 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: 1.02 in precipitation 1.0 OctNovember: 2.17 in precipitation 2.2 NovDecember: 4.49 in precipitation 4.5 Dec

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

Nearby ZIP codes

All 8 nearest ZIP codes share zone 9b.

945729b
Rodeo, CA · 2 mi
945699b
Port Costa, CA · 2 mi
945479b
Hercules, CA · 3 mi
945909b
Vallejo, CA · 3 mi
945929b
Vallejo, CA · 4 mi
945649b
Pinole, CA · 5 mi
945919b
Vallejo, CA · 6 mi
948209b
El Sobrante, CA · 6 mi

California planting zones →

Questions about 94525

What planting zone is ZIP code 94525?

ZIP code 94525 (Crockett, 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).

How much rain and snow does 94525 get?

About 21.5 inches of precipitation a year (NOAA 1991–2020 normals, Vallejo station).

How hot do summers get in Crockett, CA?

The average high peaks at 86 °F in August, with about 36 days a year at 90 °F or more.

What kind of soil does 94525 have?

The USDA soil survey maps Sehorn at the center of ZIP 94525: clay, well drained, pH about 6.7 (neutral).

Did spring come early in Crockett, CA in 2026?

Spring leaf-out near 94525 came on Jan 29 in 2026, about the same as the 1991–2020 average (Jan 29), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Crockett, CA?

Intermediate onions: the longest day near 94525 is 14 h 49 min, so day-neutral types bulb best; long-day varieties may not bulb fully.