Frost dates for 85626Pirtleville, AZ
The average last spring frost in Pirtleville is March 18 and the average first fall frost is November 13, giving a typical growing season of about 235 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Mar 18
- Average first fall frost
- Nov 13
- Growing season
- 235 days
Safer after Apr 12 (1-in-10 risk)
Possible by Oct 27 (1-in-10 risk)
First frost typically in 17 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) | Mar 18 · Apr 7 · Apr 27 | Oct 20 · Nov 3 · Nov 19 | 207 days | 100% |
| Frost / freeze (32°F) | Feb 27 · Mar 18 · Apr 12 | Oct 27 · Nov 13 · Nov 30 | 235 days | 100% |
| Hard freeze (28°F) | Jan 31 · Feb 27 · Mar 24 | Nov 5 · Nov 25 · Dec 9 | 268 days | 100% |
Planting calendar for Pirtleville
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 | Feb 15 – Apr 23 |
| Tomatoes | Transplant outdoors | Apr 3 – Jul 24 |
| Peppers | Start seeds indoors | Feb 15 – Mar 18 |
| Peppers | Transplant outdoors | Apr 17 – May 18 |
| Eggplant | Start seeds indoors | Mar 4 – Apr 2 |
| Eggplant | Transplant outdoors | Apr 17 – May 18 |
| Cucumbers | Sow outdoors | Apr 17 – Aug 3 |
| Summer squash | Sow outdoors | Apr 3 – May 18 |
| Winter squash & pumpkins | Sow outdoors | Apr 17 – May 18 |
| Snap beans | Sow outdoors | Apr 3 – Aug 26 |
| Sweet corn | Sow outdoors | Apr 3 – Jul 24 |
| Watermelon & cantaloupe | Sow outdoors | Apr 17 – May 18 |
| Okra | Sow outdoors | Apr 10 – May 3 |
| Peas | Sow outdoors (spring) | Feb 15 – Apr 2 |
| Potatoes | Plant outdoors (spring) | Feb 15 – Apr 17 |
| Onions | Start seeds indoors (spring) | Jan 4 – Jan 31 |
| Onions | Transplant outdoors (spring) | Mar 4 – Apr 2 |
| Broccoli | Start seeds indoors (spring) | Jan 28 – Mar 3 |
| Broccoli | Transplant outdoors (spring) | Mar 4 – Apr 2 |
| Broccoli | Start seeds indoors (fall) | Jul 14 – Jul 24 |
| Broccoli | Transplant outdoors (fall) | Aug 13 – Aug 24 |
| Cabbage | Start seeds indoors (spring) | Jan 18 – Feb 15 |
| Cabbage | Transplant outdoors (spring) | Feb 15 – Mar 18 |
| Cabbage | Start seeds indoors (fall) | Jul 4 – Aug 3 |
| Cabbage | Transplant outdoors (fall) | Aug 3 – Sep 3 |
| Leaf lettuce | Sow outdoors (spring) | Feb 15 – May 3 |
| Leaf lettuce | Sow outdoors (fall) | Aug 3 – Sep 19 |
| Spinach | Sow outdoors (spring) | Feb 8 – Mar 24 |
| Spinach | Sow outdoors (fall) | Aug 20 – Sep 24 |
| Radishes | Sow outdoors (spring) | Feb 15 – Apr 7 |
| Radishes | Sow outdoors (fall) | Aug 3 – Oct 4 |
| Kale | Sow outdoors (spring) | Mar 4 – Mar 24 |
| Kale | Sow outdoors (fall) | Jul 27 – Sep 3 |
| Carrots | Sow outdoors (spring) | Mar 18 – May 3 |
| Carrots | Sow outdoors (fall) | Jul 4 – Aug 19 |
| Garlic | Plant outdoors (fall) | Nov 3 – Dec 4 |
Where these dates come from
ZIP code 85626 is matched to the NOAA station Douglas, AZ, 2.7 km away, at 4,040 ft elevation (67 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Douglas, AZ (used) | 4,040 ft | Mar 18 | Nov 13 |
| Douglas Bisbee Inl Ap, AZ | 4,105 ft | Apr 11 | Nov 2 |
| Mc Neal, AZ | 4,170 ft | Apr 6 | Nov 10 |
| Bisbee 1Wnw, AZ | 5,560 ft | Apr 1 | Nov 10 |
Frost dates near Pirtleville
- Douglas, AZ 85607 · last Mar 18, first Nov 13
- Mc Neal, AZ 85617 · last Mar 4, first Nov 29
- Bisbee, AZ 85603 · last Apr 1, first Nov 10
- Naco, AZ 85620 · last Apr 5, first Nov 9
- Elfrida, AZ 85610 · last Apr 6, first Nov 10
- Pearce, AZ 85625 · last Apr 14, first Nov 2
- Fort Huachuca, AZ 85670 · last Apr 14, first Nov 2
- Hereford, AZ 85615 · last Apr 5, first Nov 9
Frequently asked questions
- When is the last frost in Pirtleville, AZ?
- For ZIP code 85626, the average last spring frost (32°F) is March 18, based on NOAA 1991-2020 climate normals for the Douglas, AZ weather station. There is a 1-in-10 chance of a frost after April 12.
- When is the first frost in Pirtleville, AZ?
- The average first fall frost (32°F) is November 13. There is a 1-in-10 chance of frost by October 27, so tender plants are at risk from that point on.
- How long is the growing season in 85626?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 235 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.