Garden Climate for Spring Valley, CA 91977

Zone 10b · Frost-free in most years · Soil 69.5°F today (modeled) · See your place on the 2023 USDA zone map

This ZIP is part of La Mesa, Lemon Grove & Spring Valley, where nearby ZIPs share the same stations and zone. That page compares every ZIP in the area.

Public NOAA/USDA data, updated 2026-10-16 19:24 UTC.

USDA Plant Hardiness Zone Map · Spring Valley focus

2023 USDA Plant Hardiness Zone Map around ZIP 91977, marker at Spring Valley, CA
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USDA Plant Hardiness Zone Map, 2023. Agricultural Research Service, U.S. Department of Agriculture. Accessed from https://planthardiness.ars.usda.gov/. Rendered unaltered from the PRISM Group, Oregon State University GIS data (https://prism.oregonstate.edu, accessed 15 Oct 2026) with official zone colors. Roads (TIGER/Line 2023 primary roads), place names (2023 Gazetteer) and state lines (2023 cartographic boundaries 1:500k) are drawn on top. Source: U.S. Census Bureau.

Zone
10b
USDA 2023 · 35 to 40°F
Last frost
None
frost-free ≥9 of 10 yrs
Soil temp Modeled
69.5°F
↓ 6.8° in 7 days
Chill hours
—
starts Nov 1
Rain
1.02″
since Oct 1 · normal 0.19″

Frost dates for 91977

Frost-free in most years. No 32F freeze in at least 9 of 10 years at this station (NCEI reports no freeze dates; growing season = 365 days).

NOAA NCEI U.S. Climate Normals 1991-2020, annual/seasonal freeze probabilities (32F) · CA SAN DIEGO MONTGOMERY FLD (USW00003131) 16.7 km away 20 yrs of record · 328 ft lower than this ZIP

Newsletter · 91977

Frost alerts and planting reminders for 91977. Coming soon.

Ad strip · leaderboard 970×90 / 728×90

7-day forecast · High / Low / Rain / Frost / Wind

High wind: 1 day(s) with gusts ≥40 mph. Stake and protect transplants.
Fri 16
91° 71° gust 44 mph 💧7%
High wind
Sat 17
87° 64° gust 35 mph 💧7%
Clear
Sun 18
86° 63° gust 17 mph 💧0%
Clear
Mon 19
81° 62° gust 16 mph 💧8%
Clear
Tue 20
71° 58° gust 24 mph 💧68% · 0.05″
Rain
Wed 21
69° 56° gust 25 mph 💧68% · 0.42″
Rain
Thu 22
67° 56° gust 18 mph 💧32% · 0.10″
Clear

NOAA NWS api.weather.gov (SGX). Frost = low ≤32°F · High wind = gust ≥40 mph · 💧 = chance of precipitation and expected amount (NWS quantitative precipitation forecast; blank when NWS gives none) · Rain = chance ≥50%.

What to grow when · 91977

Calendar: San Diego County, coastal (guide Regions 1-2). Planting months from UC Master Gardeners of San Diego County; Master Gardener Association of San Diego County. Harvest months add typical days-to-harvest. This month also checks live soil temperature and the 7-day frost forecast. The harvest planner uses the same calendar. Rules: methodology.

Affiliate links (disclosed). Placeholders, no partners yet:Frost clothSoil thermometer

Questions about 91977

What USDA hardiness zone is 91977?

ZIP 91977 (Spring Valley, CA) is in USDA zone 10b (35 to 40°F average annual extreme minimum), per the 2023 USDA Plant Hardiness Zone Map.

When is the last frost in 91977?

The nearest NOAA normals station (Ca San Diego Montgomery Fld, 16.7 km) records no 32°F freeze in at least 9 of 10 years (1991–2020).

Nearby ZIP codes

91941 La Mesa 91945 Lemon Grove 91902 Bonita 92114 San Diego 91942 La Mesa 91978 Spring Valley

Sources for this page

  • Location: US Census Bureau 2023 Gazetteer, ZCTA internal point
  • Zone: USDA Plant Hardiness Zone Map 2023, ZIP datasets (USDA ARS + PRISM Climate Group, Oregon State University)
  • Frost: NOAA NCEI U.S. Climate Normals 1991-2020, annual/seasonal freeze probabilities (32F) CA SAN DIEGO MONTGOMERY FLD (USW00003131) 16.7 km away 20 yrs of record · 328 ft lower than this ZIP
  • Forecast: NOAA National Weather Service api.weather.gov (7-day forecast + gridpoint wind gusts)
  • Soil: Open-Meteo forecast API soil model (non-commercial terms)
  • Chill: Iowa Environmental Mesonet ASOS archive (NWS/FAA METAR routine + special obs; one value per clock hour)
  • Raw data: /data/zip/91977.json