Frost dates for 86029Sun Valley, AZ
The average last spring frost in Sun Valley is April 22 and the average first fall frost is October 24, giving a typical growing season of about 184 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 22
- Average first fall frost
- Oct 24
- Growing season
- 184 days
Safer after May 7 (1-in-10 risk)
Possible by Oct 12 (1-in-10 risk)
Last frost typically in 177 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) | Apr 23 · May 4 · May 21 | Oct 3 · Oct 15 · Oct 26 | 161 days | 100% |
| Frost / freeze (32°F) | Apr 8 · Apr 22 · May 7 | Oct 12 · Oct 24 · Nov 5 | 184 days | 100% |
| Hard freeze (28°F) | Mar 21 · Apr 6 · Apr 22 | Oct 19 · Nov 2 · Nov 14 | 209 days | 100% |
Planting calendar for Sun Valley
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 | Mar 22 – May 28 |
| Tomatoes | Transplant outdoors | May 8 – Jul 4 |
| Peppers | Start seeds indoors | Mar 22 – Apr 22 |
| Peppers | Transplant outdoors | May 22 – Jun 22 |
| Eggplant | Start seeds indoors | Apr 8 – May 7 |
| Eggplant | Transplant outdoors | May 22 – Jun 22 |
| Cucumbers | Sow outdoors | May 22 – Jul 14 |
| Summer squash | Sow outdoors | May 8 – Jun 22 |
| Winter squash & pumpkins | Sow outdoors | May 22 – Jun 22 |
| Snap beans | Sow outdoors | May 8 – Aug 6 |
| Sweet corn | Sow outdoors | May 8 – Jul 4 |
| Watermelon & cantaloupe | Sow outdoors | May 22 – Jun 22 |
| Okra | Sow outdoors | May 15 – Jun 7 |
| Peas | Sow outdoors (spring) | Mar 22 – May 7 |
| Potatoes | Plant outdoors (spring) | Mar 22 – May 22 |
| Onions | Start seeds indoors (spring) | Feb 8 – Mar 7 |
| Onions | Transplant outdoors (spring) | Apr 8 – May 7 |
| Broccoli | Start seeds indoors (spring) | Mar 4 – Apr 7 |
| Broccoli | Transplant outdoors (spring) | Apr 8 – May 7 |
| Broccoli | Start seeds indoors (fall) | Jun 24 – Jul 4 |
| Broccoli | Transplant outdoors (fall) | Jul 24 – Aug 4 |
| Cabbage | Start seeds indoors (spring) | Feb 22 – Mar 22 |
| Cabbage | Transplant outdoors (spring) | Mar 22 – Apr 22 |
| Cabbage | Start seeds indoors (fall) | Jun 14 – Jul 14 |
| Cabbage | Transplant outdoors (fall) | Jul 14 – Aug 14 |
| Leaf lettuce | Sow outdoors (spring) | Mar 22 – Jun 7 |
| Leaf lettuce | Sow outdoors (fall) | Jul 14 – Aug 30 |
| Spinach | Sow outdoors (spring) | Mar 15 – Apr 28 |
| Spinach | Sow outdoors (fall) | Jul 31 – Sep 4 |
| Radishes | Sow outdoors (spring) | Mar 22 – May 12 |
| Radishes | Sow outdoors (fall) | Jul 14 – Sep 14 |
| Kale | Sow outdoors (spring) | Apr 8 – Apr 28 |
| Kale | Sow outdoors (fall) | Jul 7 – Aug 14 |
| Carrots | Sow outdoors (spring) | Apr 22 – Jun 7 |
| Carrots | Sow outdoors (fall) | Jun 14 – Jul 30 |
| Garlic | Plant outdoors (fall) | Oct 14 – Nov 14 |
Where these dates come from
ZIP code 86029 is matched to the NOAA station Holbrook, AZ, 11.8 km away, at 5,085 ft elevation (210 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Holbrook, AZ (used) | 5,085 ft | Apr 22 | Oct 24 |
| Petrified Forest Np, AZ | 5,446 ft | May 4 | Oct 16 |
| Painted Desert Np, AZ | 5,760 ft | May 1 | Oct 20 |
| Snowflake, AZ | 5,642 ft | May 11 | Oct 10 |
Frost dates near Sun Valley
- Holbrook, AZ 86025 · last Apr 22, first Oct 24
- Woodruff, AZ 85942 · last Apr 22, first Oct 24
- Joseph City, AZ 86032 · last Apr 22, first Oct 24
- Indian Wells, AZ 86031 · last May 1, first Oct 20
- Snowflake, AZ 85937 · last May 11, first Oct 10
- Petrified Forest Natl Pk, AZ 86028 · last May 22, first Oct 8
- Chambers, AZ 86502 · last May 22, first Oct 8
- Red Valley, AZ 86544 · last May 22, first Oct 8
Frequently asked questions
- When is the last frost in Sun Valley, AZ?
- For ZIP code 86029, the average last spring frost (32°F) is April 22, based on NOAA 1991-2020 climate normals for the Holbrook, AZ weather station. There is a 1-in-10 chance of a frost after May 7.
- When is the first frost in Sun Valley, AZ?
- The average first fall frost (32°F) is October 24. There is a 1-in-10 chance of frost by October 12, so tender plants are at risk from that point on.
- How long is the growing season in 86029?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 184 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.