Frost dates for 85123Arizona City, AZ
The average last spring frost in Arizona City is February 28 and the average first fall frost is November 21, giving a typical growing season of about 266 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Feb 28
- Average first fall frost
- Nov 21
- Growing season
- 266 days
Safer after Mar 14 (1-in-10 risk)
Possible by Nov 5 (1-in-10 risk)
First frost typically in 26 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Feb 27 · Mar 17 · Apr 4 | Oct 25 · Nov 12 · Nov 24 | 238 days | 100% |
| Frost / freeze (32°F) | Feb 3 · Feb 28 · Mar 14 | Nov 5 · Nov 21 · Dec 6 | 266 days | 100% |
| Hard freeze (28°F) | Jan 10 · Feb 6 · Mar 1 | Nov 16 · Dec 4 · Dec 21 | 300 days | 100% |
Planting calendar for Arizona City
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Jan 28 – Apr 5 |
| Tomatoes | Transplant outdoors | Mar 16 – Aug 1 |
| Peppers | Start seeds indoors | Jan 28 – Feb 28 |
| Peppers | Transplant outdoors | Mar 30 – Apr 30 |
| Eggplant | Start seeds indoors | Feb 14 – Mar 15 |
| Eggplant | Transplant outdoors | Mar 30 – Apr 30 |
| Cucumbers | Sow outdoors | Mar 30 – Aug 11 |
| Summer squash | Sow outdoors | Mar 16 – Apr 30 |
| Winter squash & pumpkins | Sow outdoors | Mar 30 – Apr 30 |
| Snap beans | Sow outdoors | Mar 16 – Sep 3 |
| Sweet corn | Sow outdoors | Mar 16 – Aug 1 |
| Watermelon & cantaloupe | Sow outdoors | Mar 30 – Apr 30 |
| Okra | Sow outdoors | Mar 23 – Apr 15 |
| Peas | Sow outdoors (spring) | Jan 28 – Mar 15 |
| Potatoes | Plant outdoors (spring) | Jan 28 – Mar 30 |
| Onions | Start seeds indoors (spring) | Dec 17 – Jan 13 |
| Onions | Transplant outdoors (spring) | Feb 14 – Mar 15 |
| Broccoli | Start seeds indoors (spring) | Jan 10 – Feb 13 |
| Broccoli | Transplant outdoors (spring) | Feb 14 – Mar 15 |
| Broccoli | Start seeds indoors (fall) | Jul 22 – Aug 1 |
| Broccoli | Transplant outdoors (fall) | Aug 21 – Sep 1 |
| Cabbage | Start seeds indoors (spring) | Dec 31 – Jan 28 |
| Cabbage | Transplant outdoors (spring) | Jan 28 – Feb 28 |
| Cabbage | Start seeds indoors (fall) | Jul 12 – Aug 11 |
| Cabbage | Transplant outdoors (fall) | Aug 11 – Sep 11 |
| Leaf lettuce | Sow outdoors (spring) | Jan 28 – Apr 15 |
| Leaf lettuce | Sow outdoors (fall) | Aug 11 – Sep 27 |
| Spinach | Sow outdoors (spring) | Jan 21 – Mar 6 |
| Spinach | Sow outdoors (fall) | Aug 28 – Oct 2 |
| Radishes | Sow outdoors (spring) | Jan 28 – Mar 20 |
| Radishes | Sow outdoors (fall) | Aug 11 – Oct 12 |
| Kale | Sow outdoors (spring) | Feb 14 – Mar 6 |
| Kale | Sow outdoors (fall) | Aug 4 – Sep 11 |
| Carrots | Sow outdoors (spring) | Feb 28 – Apr 15 |
| Carrots | Sow outdoors (fall) | Jul 12 – Aug 27 |
| Garlic | Plant outdoors (fall) | Nov 11 – Dec 12 |
Where these dates come from
ZIP code 85123 is matched to the NOAA station Arizona City, AZ, 3.4 km away, at 1,525 ft elevation (22 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Arizona City, AZ (used) | 1,525 ft | Feb 28 | Nov 21 |
| Robson Rch, AZ | 1,495 ft | Feb 7 | Dec 3 |
| Eloy 4 Ne, AZ | 1,545 ft | Feb 24 | Nov 28 |
| Casa Grande, AZ | 1,400 ft | Feb 5 | Dec 6 |
Frost dates near Arizona City
- Casa Grande, AZ 85130 · last Feb 5, first Dec 6
- Eloy, AZ 85131 · last Feb 24, first Nov 28
- Picacho, AZ 85141 · last Feb 6, first Dec 9
- Coolidge, AZ 85128 · last Feb 17, first Nov 29
- Stanfield, AZ 85172 · last Feb 5, first Dec 6
- Valley Farms, AZ 85191 · last Feb 17, first Nov 29
- Red Rock, AZ 85145 · last Feb 6, first Dec 9
- Maricopa, AZ 85138 · last Feb 23, first Nov 24
Frequently asked questions
- When is the last frost in Arizona City, AZ?
- For ZIP code 85123, the average last spring frost (32°F) is February 28, based on NOAA 1991-2020 climate normals for the Arizona City, AZ weather station. There is a 1-in-10 chance of a frost after March 14.
- When is the first frost in Arizona City, AZ?
- The average first fall frost (32°F) is November 21. There is a 1-in-10 chance of frost by November 5, so tender plants are at risk from that point on.
- How long is the growing season in 85123?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 266 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.