Frost dates · USDA zone 9b

Frost dates for San Jose, CA

San Jose, CA sees its last 32 °F night of spring around January 2 and its first of fall around December 25 — a 362-day freeze-free season in a typical year.

Jan 2Last spring frostmedian · 1 in 10 years after Jan 23
Dec 25First fall frostmedian · 1 in 10 years before Dec 4
362Freeze-free daysmedian year · ≥335 in 9 of 10
9bUSDA zone2023 map · ZIP 95121
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Pick a sauce; the Plan Builder runs this station's dates and hands back the calendar, plant count and gear list.

Freeze odds, by date

OddsLast spring freeze afterFirst fall freeze before
9 years in 10Dec 14 (prior winter)Jan 14 (next year)
Median — 1 year in 2Jan 2Dec 25
1 year in 10Jan 23Dec 4

The top row is the risky edge: in 9 years of 10 a spring freeze still comes after it, so tender transplants set out then need cover. The bottom row is the cautious date — only 1 year in 10 freezes after it — and the one to plan uncovered tender transplants against. Freeze-free season: 362 days median, at least 335 in 9 years of 10, no freeze at all in 1 year of 10. NOAA ranks season length year by year, so it is not the gap between two rows above.

San Jose planting calendar, 2027

Every row runs from the median last frost (Jan 2) and median first frost (Dec 25) above, using each cultivar's days to maturity. Same engine as the Plan Builder.

CropStart indoorsTransplant / plantFirst harvestDays
Hardneck GarlicSiberian (porcelain hardneck)—Oct 15prior fallJun 12240 from sow
Spanish OnionYellow Sweet Spanish (long-day)Oct 10Dec 5Mar 25110 from transplant
Mustard greensGarnet Giant (Brassica juncea)Direct sowJan 2Feb 130 from sow
CilantroSlow Bolt (Coriandrum sativum)Dec 19Dec 19Feb 245 from sow
Genovese BasilGenoveseDec 5Jan 16Mar 1760 from transplant
CayenneLong Slim Cayenne (Capsicum annuum)Nov 7Jan 9Mar 2575 from transplant
HabaneroOrange Habanero (Capsicum chinense)Oct 24Jan 16Apr 2195 from transplant
JalapeñoEarly Jalapeño (Capsicum annuum)Nov 7Jan 9Mar 2575 from transplant
Marconi Red PepperMarconi Red (Capsicum annuum)Nov 7Jan 9Mar 3080 from transplant
SerranoSerrano Tampiqueño (Capsicum annuum)Nov 7Jan 9Mar 3080 from transplant
Nantes CarrotScarlet NantesDec 19Dec 19Feb 2770 from sow
TomatilloToma VerdeNov 21Jan 9Mar 2070 from transplant
Roma TomatoRoma VF (determinate paste)Nov 21Jan 9Mar 2575 from transplant
San Marzano TomatoSan Marzano (indeterminate paste)Nov 21Jan 9Mar 3080 from transplant

Tight means first harvest lands within two weeks of the median first fall frost: start that crop indoors on time or cover it in fall.

San Jose frost questions

When is the last frost in San Jose, CA?

The median last 32 °F freeze at SAN JOSE, CA is January 2: half of years see a later one. One year in ten, a freeze still comes after January 23; nine years in ten, it comes after December 14 (prior winter). Source: NOAA NCEI 1991–2020 U.S. Climate Normals.

When is the first frost in San Jose, CA?

The median first 32 °F freeze of fall is December 25. One year in ten it arrives before December 4; nine years in ten, before January 14 (next year).

How long is the growing season in San Jose, CA?

362 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 335 days; one year in ten, no freeze at all.

What growing zone is San Jose, CA?

USDA hardiness zone 9b, per the 2023 USDA Plant Hardiness Zone Map for ZIP 95121. A zone describes the coldest winter night, not when frost ends, so it is the wrong number for a planting calendar — the frost dates on this page are the right one.

When should I plant tomatoes in San Jose, CA?

Start Roma VF (determinate paste) seeds indoors around Nov 21 and transplant around Jan 9, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for Jan 23. First ripe fruit lands around Mar 25.

When should I plant peppers in San Jose, CA?

Sow jalapeño indoors on a heat mat around Nov 7; transplant no earlier than Jan 9, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Mar 25.

Nearby in California

All California frost dates → · How frost-date math drives a sowing calendar →