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USDA hardiness zone lookup

Pasadena, CA — USDA Zone 10a

Pasadena, California · 312-day growing season

Frost dates and growing season in Pasadena

USDA hardiness zoneZone 10a
Average last spring frostFebruary 1
Average first fall frostDecember 10
Growing season length~312 days
Temperature range (F)30 to 40°F
Temperature range (C)-1 to 4°C

All of Pasadena's mapped ZIP codes fall in the same hardiness band, Zone 10a.

These are 50%-probability averages modeled from Pasadena's USDA hardiness zone and regional climate normals — not a single-station reading. In a typical year the last spring frost will have passed by February 1, but a colder-than-average year can run 1-2 weeks later. Plant tender crops (tomatoes, peppers, basil) once both soil and night temperatures are consistently warm — a thermometer beats the calendar.

Growing season in Pasadena

Pasadena, California sits in USDA Zone 10a, with roughly 312 frost-free days between an average last spring frost around February 1 and a first fall frost around December 10. That is a near year-round season — the limiting factor is summer heat, not frost, so schedule cool-season crops for winter and protect tender ones from extreme highs.

What grows in Pasadena

Pasadena falls in USDA Zone 10a, so the same hardiness constraints apply as the full Zone 10 guide. Vegetables, herbs, and fruit trees rated to Zone 10a (or hardier) will overwinter here in a typical year.

What to plant in Pasadena this week

Warm-season tropicals do well in Pasadena right now. Watch for midsummer heat stress on tomatoes — short-day varieties or shade cloth help.

Full planting calendar for Pasadena

Crop-by-crop sowing, transplant, and harvest dates calibrated to zone 10 averages:

ZIP codes in Pasadena

Drill down to the precise frost window and planting calendar for a specific ZIP in Pasadena:

Local microclimate notes

Zone tables give you the average — but Pasadenagardens vary. South-facing walls and paved areas can run a full half-zone warmer than the published rating. Low-lying spots, frost pockets, and shaded north sides can run colder. If you've gardened here a few seasons, your own frost record — the last time you actually got frost damage — beats any national average.

Source and methodology

Hardiness zone from the USDA Plant Hardiness Zone Map (2023 revision). Frost-date and growing-season figures are modeled from Pasadena's USDA hardiness zone and regional NOAA 1991-2020 climate normals — zone-level estimates, not a per-station record, so treat them as planning guidance and confirm against your own local frost history. Crop recommendations draw on US Cooperative Extension references, curated by the Growli editorial team. Last reviewed June 2026.

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