Frost dates · USDA zone 9b

Frost dates for Surprise, AZ

Surprise, AZ sees its last 32 °F night of spring around February 5 and its first of fall around December 11 — a 306-day freeze-free season in a typical year.

Feb 5Last spring frostmedian · 1 in 10 years after Mar 3
Dec 11First fall frostmedian · 1 in 10 years before Nov 20
306Freeze-free daysmedian year · ≥270 in 9 of 10
9bUSDA zone2023 map · ZIP 85387
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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 10Jan 6Jan 2 (next year)
Median — 1 year in 2Feb 5Dec 11
1 year in 10Mar 3Nov 20

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: 306 days median, at least 270 in 9 years of 10, at least 341 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 Jan 15 and first of Dec 27.

Surprise planting calendar, 2027

Every row runs from the median last frost (Feb 5) and median first frost (Dec 11) 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)Nov 13Jan 8Apr 28110 from transplant
Mustard greensGarnet Giant (Brassica juncea)Direct sowFeb 5Mar 730 from sow
CilantroSlow Bolt (Coriandrum sativum)Jan 22Jan 22Mar 845 from sow
Genovese BasilGenoveseJan 8Feb 19Apr 2060 from transplant
CayenneLong Slim Cayenne (Capsicum annuum)Dec 11Feb 12Apr 2875 from transplant
HabaneroOrange Habanero (Capsicum chinense)Nov 27Feb 19May 2595 from transplant
JalapeñoEarly Jalapeño (Capsicum annuum)Dec 11Feb 12Apr 2875 from transplant
Marconi Red PepperMarconi Red (Capsicum annuum)Dec 11Feb 12May 380 from transplant
SerranoSerrano Tampiqueño (Capsicum annuum)Dec 11Feb 12May 380 from transplant
Nantes CarrotScarlet NantesJan 22Jan 22Apr 270 from sow
TomatilloToma VerdeDec 25Feb 12Apr 2370 from transplant
Roma TomatoRoma VF (determinate paste)Dec 25Feb 12Apr 2875 from transplant
San Marzano TomatoSan Marzano (indeterminate paste)Dec 25Feb 12May 380 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.

Surprise frost questions

When is the last frost in Surprise, AZ?

The median last 32 °F freeze at WITTMANN 1SE, AZ is February 5: half of years see a later one. One year in ten, a freeze still comes after March 3; nine years in ten, it comes after January 6. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.

When is the first frost in Surprise, AZ?

The median first 32 °F freeze of fall is December 11. One year in ten it arrives before November 20; nine years in ten, before January 2 (next year).

How long is the growing season in Surprise, AZ?

306 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 270 days; one year in ten, at least 341 days.

What growing zone is Surprise, AZ?

USDA hardiness zone 9b, per the 2023 USDA Plant Hardiness Zone Map for ZIP 85387. 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 Surprise, AZ?

Start Roma VF (determinate paste) seeds indoors around Dec 25 and transplant around Feb 12, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for Mar 3. First ripe fruit lands around Apr 28.

When should I plant peppers in Surprise, AZ?

Sow jalapeño indoors on a heat mat around Dec 11; transplant no earlier than Feb 12, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Apr 28.

Nearby in Arizona

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