Garden Climate for Chula Vista: 91913, 91914, 91915

Zone 10b · Last frost ~Jan 6 · Soil 70.4°F today (modeled) · See your place on the 2023 USDA zone map

ZIPs in this area

What differs between these ZIPs: elevation, soil temperature. Everything else on this page is the same for all of them. The page below shows 91915 (closest to the area's middle elevation).

ZIPTownElevationZoneLast frostFirst frostChill hrs last seasonSoil now
91913Chula Vista488 ft10bJan 6Dec 315670.7°F
91914Chula Vista691 ft10bJan 6Dec 315669.8°F
91915Chula Vista531 ft10bJan 6Dec 315670.4°F

Why grouped: these are urban and suburban lowland ZIPs (under about 1,500 ft and within 40 km of the ocean) whose numbers are close: median last frost dates within about two weeks of each other, last season's chill hours all in the <100 range, the same inland setting and the same 820 ft elevation band. Each ZIP still uses its own nearest suitable stations; see the table for exact values.

Public NOAA/USDA data, updated 2026-10-16 18:57 UTC.

USDA Plant Hardiness Zone Map · Chula Vista focus

2023 USDA Plant Hardiness Zone Map around ZIP 91915, marker at Chula Vista, 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
Jan 6
avg last frost (50%)
Soil temp Modeled
70.4°F
↓ 8.6° in 7 days
Chill hours
—
starts Nov 1
Rain
1.53″
since Oct 1 · normal 0.16″

Frost dates for 91915

Last spring frost
Jan 6
50% odds
First fall frost
Dec 31
50% odds
Safer spring date
Feb 5
10% chance of later frost
Growing season
365
days (50%)

Earliest-risk fall date (10%): Dec 11.

NOAA NCEI U.S. Climate Normals 1991-2020, annual/seasonal freeze probabilities (32F) · CA SAN DIEGO BROWN FLD (USW00003178) 7.5 km away 23 yrs of record · about the same elevation

Newsletter · 91915

Frost alerts and planting reminders for 91915. Coming soon.

Ad strip · leaderboard 970×90 / 728×90

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

High wind: 2 day(s) with gusts ≥40 mph. Stake and protect transplants.
Fri 16
90° 71° gust 54 mph 💧8%
High wind
Sat 17
87° 64° gust 40 mph 💧8%
High wind
Sun 18
86° 64° gust 17 mph 💧0%
Clear
Mon 19
82° 61° gust 17 mph 💧8%
Clear
Tue 20
72° 58° gust 25 mph 💧67% · 0.05″
Rain
Wed 21
69° 56° gust 25 mph 💧67% · 0.43″
Rain
Thu 22
68° 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 · 91915

Calendar: San Diego County, inland valleys (guide Regions 3-4). 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 91915

What USDA hardiness zone is 91915?

ZIP 91915 (Chula Vista, 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 91915?

Based on NOAA 1991–2020 normals at Ca San Diego Brown Fld (7.5 km away), the median last 32°F freeze is Jan 6. In 1 of 10 years it is after Feb 5. The median first fall freeze is Dec 31.

Nearby ZIP codes

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 BROWN FLD (USW00003178) 7.5 km away 23 yrs of record · about the same elevation
  • 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: CIMIS, California Department of Water Resources (hourly air temperature; QC-flagged hours dropped)
  • Raw data: /data/zip/91915.json