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USDA hardiness zone lookup

Gilroy, CA — USDA Zone 9b

Gilroy, California · 279-day growing season

Frost dates and growing season in Gilroy

USDA hardiness zoneZone 9b
Average last spring frostFebruary 24
Average first fall frostNovember 30
Growing season length~279 days
Temperature range (F)20 to 30°F
Temperature range (C)-7 to -1°C

All of Gilroy's mapped ZIP codes fall in the same hardiness band, Zone 9b.

These are 50%-probability averages modeled from Gilroy'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 24, 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 Gilroy

Gilroy, California sits in USDA Zone 9b, with roughly 279 frost-free days between an average last spring frost around February 24 and a first fall frost around November 30. 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 Gilroy

Gilroy falls in USDA Zone 9b, so the same hardiness constraints apply as the full Zone 9 guide. Vegetables, herbs, and fruit trees rated to Zone 9b (or hardier) will overwinter here in a typical year.

What to plant in Gilroy this week

Gilroy is in high summer — most spring plantings are in. Keep an eye on watering and start planning your fall crop. Cool-season seedlings (broccoli, cabbage, lettuce) can be started indoors for a fall transplant.

Full planting calendar for Gilroy

Crop-by-crop sowing, transplant, and harvest dates calibrated to zone 9 averages:

ZIP codes in Gilroy

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

Local microclimate notes

Zone tables give you the average — but Gilroygardens 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 Gilroy'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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