Frost dates · USDA zone 10a

Frost dates for Azusa, CA

Azusa, CA sees its last 32 °F night of spring around April 28 and its first of fall around November 15 — a 199-day freeze-free season in a typical year.

Apr 28Last spring frostmedian · 1 in 10 years after May 27
Nov 15First fall frostmedian · 1 in 10 years before Oct 18
199Freeze-free daysmedian year · ≥164 in 9 of 10
10aUSDA zone2023 map · ZIP 91010
Build a Azusa 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 10Mar 31Dec 9
Median — 1 year in 2Apr 28Nov 15
1 year in 10May 27Oct 18

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: 199 days median, at least 164 in 9 years of 10, at least 238 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 Apr 8 and first of Dec 4.

Azusa planting calendar, 2027

Every row runs from the median last frost (Apr 28) and median first frost (Nov 15) 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)Feb 3Mar 31Jul 19110 from transplant
Mustard greensGarnet Giant (Brassica juncea)Direct sowApr 28May 2830 from sow
CilantroSlow Bolt (Coriandrum sativum)Apr 14Apr 14May 2945 from sow
Genovese BasilGenoveseMar 31May 12Jul 1160 from transplant
CayenneLong Slim Cayenne (Capsicum annuum)Mar 3May 5Jul 1975 from transplant
HabaneroOrange Habanero (Capsicum chinense)Feb 17May 12Aug 1595 from transplant
JalapeñoEarly Jalapeño (Capsicum annuum)Mar 3May 5Jul 1975 from transplant
Marconi Red PepperMarconi Red (Capsicum annuum)Mar 3May 5Jul 2480 from transplant
SerranoSerrano Tampiqueño (Capsicum annuum)Mar 3May 5Jul 2480 from transplant
Nantes CarrotScarlet NantesApr 14Apr 14Jun 2370 from sow
TomatilloToma VerdeMar 17May 5Jul 1470 from transplant
Roma TomatoRoma VF (determinate paste)Mar 17May 5Jul 1975 from transplant
San Marzano TomatoSan Marzano (indeterminate paste)Mar 17May 5Jul 2480 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.

Azusa frost questions

When is the last frost in Azusa, CA?

The median last 32 °F freeze at MT WILSON CBS, CA is April 28: half of years see a later one. One year in ten, a freeze still comes after May 27; nine years in ten, it comes after March 31. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.

When is the first frost in Azusa, CA?

The median first 32 °F freeze of fall is November 15. One year in ten it arrives before October 18; nine years in ten, before December 9.

How long is the growing season in Azusa, CA?

199 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 164 days; one year in ten, at least 238 days.

What growing zone is Azusa, CA?

USDA hardiness zone 10a, per the 2023 USDA Plant Hardiness Zone Map for ZIP 91010. 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 Azusa, CA?

Start Roma VF (determinate paste) seeds indoors around Mar 17 and transplant around May 5, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for May 27. First ripe fruit lands around Jul 19.

When should I plant peppers in Azusa, CA?

Sow jalapeño indoors on a heat mat around Mar 3; transplant no earlier than May 5, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Jul 19.

Nearby in California

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