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ZIP 95113 planting calendar

When to plant basil in San Jose, CA - Zone 9b

In ZIP 95113, plant basil around Feb 25; this uses the San Jose frost station, USDA zone 9b, and basil timing rules.

Your San Jose calendar has a 289-day estimated frost-free season. This estimate uses the representative San Jose frost station, USDA zone 9b, and basil timing rules.

Source: san-jose-mineta frost station, USDA zone 9b, last updated 2026-06-28. Verify locally before planting high-value crops because microclimates, current weather, and yard exposure can move the safe date.

USDA zone 9b San Jose frost station University of California Agriculture and Natural Resources Updated 2026-06-28
Read the method

Answer first

When to start basil seeds indoors in San Jose

In ZIP 95113, start basil seeds indoors around Jan 11, about 35 days before the Feb 15 last-frost estimate.

Start basil seeds indoors in San Jose around Jan 11, about 35 days before the Feb 15 last-frost estimate.

Seed starting schedule

Basil dates for San Jose, CA

StepDateHow to use it
Start IndoorsJanuary 11, 2026Start seeds under lights or in a bright indoor seed-starting space.
Transplant OutdoorsFebruary 25, 2026Move hardened-off seedlings outside after the frost-risk window.
Direct SowFebruary 25, 2026Sow seed outside when the crop and soil can handle the window.

Last frost

When is the last frost in San Jose?

San Jose (ZIP 95113) has an average last spring frost around Feb 15.

First frost

When is the first frost in San Jose?

The average first fall frost is around Dec 1, giving about 289 frost-free days.

Season map

Basil windows by month

JanFebMarAprMayJunJulAugSepOctNovDec
Start indoors
Jan 11
Direct sow
Feb 25
Transplant
Feb 25
Harvest
May 1
Frost watch
Sep 27

Reminder workflow

Every date has a next action

Start basil indoorsJan 11
Last frost windowFeb 15
Direct sow basilFeb 25
Transplant basilFeb 25
First basil harvest windowMay 1
Last basil sowing targetSep 27
SignalValueWhy it matters
Last frost estimateFebruary 15, 2026Warm-season transplant risk starts falling after this window.
First frost estimateDecember 1, 2026Fall planting counts backward from this date.
Season length289 daysLonger seasons can support succession crops.
Spacing10-12 inAirflow and root space affect yield.
Soil temperature65 F+Seeds and transplants stall in cold soil.

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Local data

Why this date changes by ZIP

San Jose frost history and USDA zone 9b shift the safe planting window. GrowZone uses a local representative station instead of one national rule.

University of California Agriculture and Natural Resources is the kind of local source to verify against when a crop is expensive, weather is unusual, or your yard has a cold pocket.

Crop note

Basil timing notes

Pinch the growing tips early for fuller plants. Basil prefers full sun, 10-12 in spacing, and soil near 65 F+.

For fall, count backward from Dec 1. A conservative last sowing target is around Sep 27.