Fall in zone 7aPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 86435 (Supai, AZ)
Average last spring and first fall frost dates with 10%, 50% and 90% odds, from NOAA's 1991–2020 climate normals for the nearest weather station, Williams 35 NNW, AZ (38 miles away).
Station is a bit far
The nearest station with freeze normals is over 40 km away, so dates here may be off by a week or more.
- Average last spring frostMay 950% chance of a 32°F freeze after this date
- Average first fall frostOct 1950% chance of a 32°F freeze by this date
- Growing season (frost-free)161 daysmedian, 32°F threshold
- USDA hardiness zone7a0 to 5°F avg. coldest night
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This week in your yard
As of Oct 18, 2026, from your frost dates, zone and soil temperature. Lawn timing · Vegetables · Pruning · Plants
Soil temperature now
2-inch depth
48°F Below 50°F
24-hour average · latest 48°F, as of Oct 18, 1:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Williams 35 NNW (38 mi).
4-inch depth
51°F 50–55°F
24-hour average · latest 51°F, as of Oct 18, 1:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Williams 35 NNW (38 mi).
Fall: Texas A&M AgriLife times fall pre-emergent (for winter weeds such as annual bluegrass) to soil cooling to about 70°F for several days. The 50–55°F band is the spring trigger. Always read and follow the product label.
7-day forecast and frost risk
The latest National Weather Service 7-day forecast and any Frost Advisory or Freeze Warning for 86435 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 51°F at 4 inches (estimated soil temperature, not a station reading). Fall pre-emergent window is mostly past. Next: spring, when soil reaches 50°F (typically mid-April to mid-May).
Fertilizer window
Lawn region: Mountain West and High Plains. Timing only; always follow the product label.
- Kentucky bluegrass (cool-season): Early fall: Around Labor Day (late August–September); Late fall: Late October–November, before the ground freezes; Late spring: Optional around Memorial Day. Avoid: Early-spring and midsummer feeding (pushes top growth, favors crabgrass).
Plant now
No vegetable planting windows are open this week.
Prune now
No frost-timed pruning windows are open this week.
Your average first frost is Oct 19: skip heavy pruning in the 6–8 weeks before it, because new growth may not harden off in time.
Spring-flowering shrubs are pruned right after their flowers fade, not by date. See the pruning guide.
Last spring frost odds
| Chance of a 32°F freeze after this date | Date |
|---|---|
| 90% (early: most years still freeze after this) | Apr 24 |
| 50% (the "average" last frost) | May 9 |
| 10% (cautious: only 1 year in 10 freezes later) | May 27 |
Most gardeners plant frost-tender crops (tomatoes, peppers, basil) after the 50% date, and closer to the 10% date for less risk.
First fall frost odds
| Chance the first 32°F freeze has happened by this date | Date |
|---|---|
| 10% (early: 1 year in 10 freezes this soon) | Oct 3 |
| 50% (the "average" first frost) | Oct 19 |
| 90% (late: most years have frozen by now) | Nov 3 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | May 24 | Oct 6 |
| 32°F (freeze) | May 9 | Oct 19 |
| 28°F (hard freeze) | Apr 24 | Oct 31 |
n/a means NOAA did not publish a date at that threshold for this station (usually because it rarely gets that cold).
Vegetable planting calendar for 86435
Dates count from your average last spring frost (May 9) and first fall frost (Oct 19). Half of years have a frost after the spring date, so give tender crops (tomatoes, peppers, squash) some slack.
| Crop | Start indoors | Spring planting | Fall planting |
|---|---|---|---|
| Tomato | Mar 14–28 | May 16–30 (transplant) | – |
| Pepper (sweet and hot) | Feb 28–Mar 14 | May 23–Jun 6 (transplant) | – |
| Eggplant | Feb 28–Mar 14 | May 23–Jun 6 (transplant) | – |
| Tomatillo | Mar 14–28 | May 16–30 (transplant) | – |
| Lettuce | Mar 14–28 | Apr 18–May 9 (transplant) Apr 11–May 23 (sow outdoors) | Aug 24–Sep 14 (transplant) Aug 10–Sep 7 (sowing) |
| Spinach | – | Mar 28–Apr 18 (sow outdoors) | Aug 24–Sep 14 (sowing) |
| Kale | Mar 14–28 | Apr 11–25 (transplant) Apr 11–25 (sow outdoors) | Jul 27–Aug 24 (transplant) Jul 13–Aug 10 (sowing) |
| Collards | Mar 14–28 | Apr 11–May 9 (transplant) Apr 11–May 9 (sow outdoors) | Jul 27–Aug 24 (transplant) Jul 13–Aug 10 (sowing) |
| Broccoli | Feb 28–Mar 14 | Apr 11–25 (transplant) | Jul 13–Aug 10 (transplant) |
| Cabbage | Feb 28–Mar 14 | Apr 11–25 (transplant) | Jul 13–Aug 10 (transplant) |
| Cauliflower | Feb 28–Mar 14 | Apr 25–May 9 (transplant) | Jul 13–Aug 10 (transplant) |
| Brussels sprouts | Feb 14–28 | Apr 11–25 (transplant) | Jun 29–Jul 20 (transplant) |
| Kohlrabi | Mar 14–28 | Apr 11–25 (transplant) Apr 11–25 (sow outdoors) | Aug 10–24 (sowing) |
| Bok choy / Asian greens | – | Apr 11–25 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Arugula | – | Apr 11–May 9 (sow outdoors) | Aug 24–Sep 21 (sowing) |
| Mustard greens | – | Apr 11–May 2 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Swiss chard | Mar 28–Apr 11 | Apr 25–May 16 (transplant) Apr 25–May 23 (sow outdoors) | Aug 10–24 (sowing) |
| Beet | – | Apr 11–May 9 (sow outdoors) | Aug 10–24 (sowing) |
| Carrot | – | Apr 18–May 16 (sow outdoors) | Jul 27–Aug 10 (sowing) |
| Radish | – | Apr 4–May 16 (sow outdoors) | Sep 7–21 (sowing) |
| Turnip | – | Apr 11–May 2 (sow outdoors) | Aug 10–24 (sowing) |
| Parsnip | – | Apr 18–May 9 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Mar 14–Apr 11 (sow outdoors) | Jul 27–Aug 10 (sowing) |
| Onion (bulbing) | Feb 14–28 | Mar 28–Apr 11 (transplant) | – |
| Green onion / scallion | – | Mar 28–Apr 25 (sow outdoors) | Aug 10–24 (sowing) |
| Leek | Feb 14–28 | Apr 11–25 (transplant) | – |
| Garlic | – | – | Sep 7–Oct 5 (sowing) |
| Shallot | – | Mar 28–Apr 11 (transplant) | Sep 7–Oct 5 (sowing) |
| Potato | – | Apr 11–25 (transplant) | Jun 29–Jul 13 (transplant) |
| Sweet potato | – | May 30–Jun 13 (transplant) | – |
| Sweet corn | – | May 16–30 (sow outdoors) | – |
| Bean, bush (snap) | – | May 16–30 (sow outdoors) | – |
| Bean, pole | – | May 16–30 (sow outdoors) | – |
| Lima bean | – | May 23–Jun 6 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 30–Jun 20 (sow outdoors) | – |
| Cucumber | Apr 11–18 | May 16–30 (transplant) May 16–30 (sow outdoors) | – |
| Summer squash / zucchini | Apr 11–18 | May 16–30 (transplant) May 16–30 (sow outdoors) | – |
| Winter squash | Apr 11–18 | May 16–30 (transplant) May 16–30 (sow outdoors) | – |
| Pumpkin | – | May 16–30 (sow outdoors) | – |
| Watermelon | Apr 11–18 | May 23–Jun 6 (transplant) May 23–Jun 6 (sow outdoors) | – |
| Cantaloupe / muskmelon | Apr 11–18 | May 23–Jun 6 (transplant) May 23–Jun 6 (sow outdoors) | – |
| Okra | Mar 28–Apr 11 | May 23–Jun 6 (transplant) May 23–Jun 6 (sow outdoors) | – |
| Celery | Feb 14–28 | May 16–23 (transplant) | – |
| Basil | Mar 28–Apr 11 | May 16–30 (transplant) May 16–30 (sow outdoors) | – |
| Cilantro | – | Apr 25–May 23 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Parsley | Feb 28–Mar 14 | Apr 25–May 9 (transplant) Apr 18–May 9 (sow outdoors) | – |
| Dill | – | May 9–23 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Sunflower | – | May 9–23 (sow outdoors) | – |
| Asparagus (crowns) | – | Apr 11–25 (transplant) | – |
| Rhubarb (crowns) | – | Apr 11–25 (transplant) | – |
| Strawberry (plants) | – | Apr 11–25 (transplant) | Aug 10–Sep 7 (transplant) |
Typical ranges from university extension planting calendars, adjusted to your frost dates. Probabilities, not guarantees. Fall windows that would overlap spring planting are left out, as are fall crops of frost-tender plants where the frost-free season is under 210 days.
Where these numbers come from
Station: Williams 35 NNW, AZ (NOAA GHCN-Daily ID USW00053155), elevation 5,990 ft, 38.2 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Grand Canyon Np AP, AZ | 44 mi | Jun 17 | Sep 24 |
| Grand Canyon Np 2, AZ | 45 mi | Jun 1 | Oct 3 |
| Seligman, AZ | 47 mi | May 10 | Oct 15 |
The average last-frost dates of these stations span 39 days, a rough guide to local variation. See data sources & methods.
Frost questions for 86435
When is the last frost in 86435?
The average (50% chance) last spring freeze of 32°F for ZIP 86435 is May 9. For a more cautious planting date, use May 27, when only 1 year in 10 still sees a later freeze.
When is the first frost in 86435?
The average first fall freeze is October 19. In 1 year in 10 it comes by October 3.
What hardiness zone is 86435?
ZIP 86435 is in USDA zone 7a (0 to 5°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 86435 right now?
This page shows the latest 2-inch and 4-inch soil temperature from the nearest public soil station (USDA SCAN, NOAA USCRN or TexMesonet), or a labeled estimate when no station is close, against the 50–55°F spring pre-emergent band.
Nearby ZIP codes
86434 Grand Canyon West 86320 Kaibab Estates West 86052 86023 Grand Canyon Village 86337 Seligman 86437 Valentine 86022 Fredonia 86046 Valle
Other ZIP codes in Coconino County
85931 86001 86003 86004 86005 86011 86015 86016 86017 86018 86020 86022 86023 86024 86030 86035 86036 86038 86040 86044 86045 86046 86052 86053 All Coconino County frost dates · Arizona frost dates
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Weekly yard timing, plus frost and soil-temperature alerts for your ZIP code.
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Free. One weekly email plus alerts when your ZIP has a frost or a soil-temperature change worth acting on. After you submit, Kit (our email provider) sends a confirmation email: check your email and click the link to confirm. You aren't subscribed until you do. We collect only your email address and ZIP, sent to Kit to deliver The Dial. Unsubscribe anytime.