Frost dates · USDA zone 9b

Frost dates for Chico, CA

Chico, CA sees its last 32 °F night of spring around March 4 and its first of fall around November 17 — a 257-day freeze-free season in a typical year.

Mar 4Last spring frostmedian · 1 in 10 years after Apr 2
Nov 17First fall frostmedian · 1 in 10 years before Nov 1
257Freeze-free daysmedian year · ≥223 in 9 of 10
9bUSDA zone2023 map · ZIP 95926
Build a Chico sauce plan →

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 10Feb 8Dec 5
Median — 1 year in 2Mar 4Nov 17
1 year in 10Apr 2Nov 1

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: 257 days median, at least 223 in 9 years of 10, at least 290 days in 1 year of 10. NOAA ranks season length year by year, so it is not the gap between two rows above. A hard freeze (28 °F) has a median last date of Feb 5 and first of Dec 3.

Chico planting calendar, 2027

Every row runs from the median last frost (Mar 4) and median first frost (Nov 17) 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)Dec 10Feb 4May 25110 from transplant
Mustard greensGarnet Giant (Brassica juncea)Direct sowMar 4Apr 330 from sow
CilantroSlow Bolt (Coriandrum sativum)Feb 18Feb 18Apr 445 from sow
Genovese BasilGenoveseFeb 4Mar 18May 1760 from transplant
CayenneLong Slim Cayenne (Capsicum annuum)Jan 7Mar 11May 2575 from transplant
HabaneroOrange Habanero (Capsicum chinense)Dec 24Mar 18Jun 2195 from transplant
JalapeñoEarly Jalapeño (Capsicum annuum)Jan 7Mar 11May 2575 from transplant
Marconi Red PepperMarconi Red (Capsicum annuum)Jan 7Mar 11May 3080 from transplant
SerranoSerrano Tampiqueño (Capsicum annuum)Jan 7Mar 11May 3080 from transplant
Nantes CarrotScarlet NantesFeb 18Feb 18Apr 2970 from sow
TomatilloToma VerdeJan 21Mar 11May 2070 from transplant
Roma TomatoRoma VF (determinate paste)Jan 21Mar 11May 2575 from transplant
San Marzano TomatoSan Marzano (indeterminate paste)Jan 21Mar 11May 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.

Chico frost questions

When is the last frost in Chico, CA?

The median last 32 °F freeze at CHICO UNIV FARM, CA is March 4: half of years see a later one. One year in ten, a freeze still comes after April 2; nine years in ten, it comes after February 8. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.

When is the first frost in Chico, CA?

The median first 32 °F freeze of fall is November 17. One year in ten it arrives before November 1; nine years in ten, before December 5.

How long is the growing season in Chico, CA?

257 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 223 days; one year in ten, at least 290 days.

What growing zone is Chico, CA?

USDA hardiness zone 9b, per the 2023 USDA Plant Hardiness Zone Map for ZIP 95926. 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 Chico, CA?

Start Roma VF (determinate paste) seeds indoors around Jan 21 and transplant around Mar 11, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for Apr 2. First ripe fruit lands around May 25.

When should I plant peppers in Chico, CA?

Sow jalapeño indoors on a heat mat around Jan 7; transplant no earlier than Mar 11, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around May 25.

Nearby in California

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