Frost dates · USDA zone 9a
Frost dates for Casa Grande, AZ
Casa Grande, AZ sees its last 32 °F night of spring around February 5 and its first of fall around December 6 — a 305-day freeze-free season in a typical year.
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
| Odds | Last spring freeze after | First fall freeze before |
|---|---|---|
| 9 years in 10 | Jan 5 | Dec 29 |
| Median — 1 year in 2 | Feb 5 | Dec 6 |
| 1 year in 10 | Feb 28 | Nov 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: 305 days median, at least 273 in 9 years of 10, at least 340 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 14 and first of Dec 22.
Casa Grande planting calendar, 2027
Every row runs from the median last frost (Feb 5) and median first frost (Dec 6) above, using each cultivar's days to maturity. Same engine as the Plan Builder.
| Crop | Start indoors | Transplant / plant | First harvest | Days |
|---|---|---|---|---|
| Hardneck GarlicSiberian (porcelain hardneck) | — | Oct 15prior fall | Jun 12 | 240 from sow |
| Spanish OnionYellow Sweet Spanish (long-day) | Nov 13 | Jan 8 | Apr 28 | 110 from transplant |
| Mustard greensGarnet Giant (Brassica juncea) | Direct sow | Feb 5 | Mar 7 | 30 from sow |
| CilantroSlow Bolt (Coriandrum sativum) | Jan 22 | Jan 22 | Mar 8 | 45 from sow |
| Genovese BasilGenovese | Jan 8 | Feb 19 | Apr 20 | 60 from transplant |
| CayenneLong Slim Cayenne (Capsicum annuum) | Dec 11 | Feb 12 | Apr 28 | 75 from transplant |
| HabaneroOrange Habanero (Capsicum chinense) | Nov 27 | Feb 19 | May 25 | 95 from transplant |
| JalapeñoEarly Jalapeño (Capsicum annuum) | Dec 11 | Feb 12 | Apr 28 | 75 from transplant |
| Marconi Red PepperMarconi Red (Capsicum annuum) | Dec 11 | Feb 12 | May 3 | 80 from transplant |
| SerranoSerrano Tampiqueño (Capsicum annuum) | Dec 11 | Feb 12 | May 3 | 80 from transplant |
| Nantes CarrotScarlet Nantes | Jan 22 | Jan 22 | Apr 2 | 70 from sow |
| TomatilloToma Verde | Dec 25 | Feb 12 | Apr 23 | 70 from transplant |
| Roma TomatoRoma VF (determinate paste) | Dec 25 | Feb 12 | Apr 28 | 75 from transplant |
| San Marzano TomatoSan Marzano (indeterminate paste) | Dec 25 | Feb 12 | May 3 | 80 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.
What sauce can Casa Grande grow?
Each sauce, scheduled for a Casa Grande container garden: when the first seeds go in and when enough fruit has ripened for one batch.
Casa Grande frost questions
When is the last frost in Casa Grande, AZ?
The median last 32 °F freeze at CASA GRANDE, AZ is February 5: half of years see a later one. One year in ten, a freeze still comes after February 28; nine years in ten, it comes after January 5. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.
When is the first frost in Casa Grande, AZ?
The median first 32 °F freeze of fall is December 6. One year in ten it arrives before November 18; nine years in ten, before December 29.
How long is the growing season in Casa Grande, AZ?
305 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 273 days; one year in ten, at least 340 days.
What growing zone is Casa Grande, AZ?
USDA hardiness zone 9a, per the 2023 USDA Plant Hardiness Zone Map for ZIP 85122. 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 Casa Grande, 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 Feb 28. First ripe fruit lands around Apr 28.
When should I plant peppers in Casa Grande, 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
- Maricopalast frost Feb 23
- Queen Creeklast frost Feb 1
- Chandlerlast frost Feb 1
- Gilbertlast frost Feb 1
- Mesalast frost Feb 1
- Tempelast frost Feb 13
All Arizona frost dates → · How frost-date math drives a sowing calendar →