Fall in zone 6bPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 86038 (Mormon Lake, 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, Mund's Park, AZ (9 miles away).
- Average last spring frostJun 1050% chance of a 32°F freeze after this date
- Average first fall frostSep 2750% chance of a 32°F freeze by this date
- Growing season (frost-free)106 daysmedian, 32°F threshold
- USDA hardiness zone6b-5 to 0°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
No soil station with a fresh reading within 62 miles.
4-inch depth
No soil station with a fresh reading within 62 miles.
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 86038 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
No soil reading near this ZIP. Typical extension timing for your region: spring 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.
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) | May 26 |
| 50% (the "average" last frost) | Jun 10 |
| 10% (cautious: only 1 year in 10 freezes later) | Jun 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) | Sep 14 |
| 50% (the "average" first frost) | Sep 27 |
| 90% (late: most years have frozen by now) | Oct 8 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | Jun 24 | Sep 17 |
| 32°F (freeze) | Jun 10 | Sep 27 |
| 28°F (hard freeze) | May 26 | Oct 7 |
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 86038
Dates count from your average last spring frost (Jun 10) and first fall frost (Sep 27). 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 | Apr 15–29 | Jun 17–Jul 1 (transplant) | – |
| Pepper (sweet and hot) | Apr 1–15 | Jun 24–Jul 8 (transplant) | – |
| Eggplant | Apr 1–15 | Jun 24–Jul 8 (transplant) | – |
| Tomatillo | Apr 15–29 | Jun 17–Jul 1 (transplant) | – |
| Lettuce | Apr 15–29 | May 20–Jun 10 (transplant) May 13–Jun 24 (sow outdoors) | Aug 2–23 (transplant) Jul 19–Aug 16 (sowing) |
| Spinach | – | Apr 29–May 20 (sow outdoors) | Aug 2–23 (sowing) |
| Kale | Apr 15–29 | May 13–27 (transplant) May 13–27 (sow outdoors) | Jul 5–Aug 2 (transplant) Jun 21–Jul 19 (sowing) |
| Collards | Apr 15–29 | May 13–Jun 10 (transplant) May 13–Jun 10 (sow outdoors) | Jul 5–Aug 2 (transplant) Jun 21–Jul 19 (sowing) |
| Broccoli | Apr 1–15 | May 13–27 (transplant) | Jun 21–Jul 19 (transplant) |
| Cabbage | Apr 1–15 | May 13–27 (transplant) | Jun 21–Jul 19 (transplant) |
| Cauliflower | Apr 1–15 | May 27–Jun 10 (transplant) | Jun 21–Jul 19 (transplant) |
| Brussels sprouts | Mar 18–Apr 1 | May 13–27 (transplant) | Jun 7–28 (transplant) |
| Kohlrabi | Apr 15–29 | May 13–27 (transplant) May 13–27 (sow outdoors) | Jul 19–Aug 2 (sowing) |
| Bok choy / Asian greens | – | May 13–27 (sow outdoors) | Aug 2–16 (sowing) |
| Arugula | – | May 13–Jun 10 (sow outdoors) | Aug 2–30 (sowing) |
| Mustard greens | – | May 13–Jun 3 (sow outdoors) | Aug 2–16 (sowing) |
| Swiss chard | Apr 29–May 13 | May 27–Jun 17 (transplant) May 27–Jun 24 (sow outdoors) | Jul 19–Aug 2 (sowing) |
| Beet | – | May 13–Jun 10 (sow outdoors) | Jul 19–Aug 2 (sowing) |
| Carrot | – | May 20–Jun 17 (sow outdoors) | Jul 5–19 (sowing) |
| Radish | – | May 6–Jun 17 (sow outdoors) | Aug 16–30 (sowing) |
| Turnip | – | May 13–Jun 3 (sow outdoors) | Jul 19–Aug 2 (sowing) |
| Parsnip | – | May 20–Jun 10 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Apr 15–May 13 (sow outdoors) | Jul 5–19 (sowing) |
| Onion (bulbing) | Mar 18–Apr 1 | Apr 29–May 13 (transplant) | – |
| Green onion / scallion | – | Apr 29–May 27 (sow outdoors) | Jul 19–Aug 2 (sowing) |
| Leek | Mar 18–Apr 1 | May 13–27 (transplant) | – |
| Garlic | – | – | Aug 16–Sep 13 (sowing) |
| Shallot | – | Apr 29–May 13 (transplant) | Aug 16–Sep 13 (sowing) |
| Potato | – | May 13–27 (transplant) | Jun 7–21 (transplant) |
| Sweet potato | – | Jul 1–15 (transplant) | – |
| Sweet corn | – | Jun 17–Jul 1 (sow outdoors) | – |
| Bean, bush (snap) | – | Jun 17–Jul 1 (sow outdoors) | – |
| Bean, pole | – | Jun 17–Jul 1 (sow outdoors) | – |
| Lima bean | – | Jun 24–Jul 8 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Jul 1–22 (sow outdoors) | – |
| Cucumber | May 13–20 | Jun 17–Jul 1 (transplant) Jun 17–Jul 1 (sow outdoors) | – |
| Summer squash / zucchini | May 13–20 | Jun 17–Jul 1 (transplant) Jun 17–Jul 1 (sow outdoors) | – |
| Winter squash | May 13–20 | Jun 17–Jul 1 (transplant) Jun 17–Jul 1 (sow outdoors) | – |
| Pumpkin | – | Jun 17–Jul 1 (sow outdoors) | – |
| Watermelon | May 13–20 | Jun 24–Jul 8 (transplant) Jun 24–Jul 8 (sow outdoors) | – |
| Cantaloupe / muskmelon | May 13–20 | Jun 24–Jul 8 (transplant) Jun 24–Jul 8 (sow outdoors) | – |
| Okra | Apr 29–May 13 | Jun 24–Jul 8 (transplant) Jun 24–Jul 8 (sow outdoors) | – |
| Celery | Mar 18–Apr 1 | Jun 17–24 (transplant) | – |
| Basil | Apr 29–May 13 | Jun 17–Jul 1 (transplant) Jun 17–Jul 1 (sow outdoors) | – |
| Cilantro | – | May 27–Jun 24 (sow outdoors) | Aug 2–16 (sowing) |
| Parsley | Apr 1–15 | May 27–Jun 10 (transplant) May 20–Jun 10 (sow outdoors) | – |
| Dill | – | Jun 10–24 (sow outdoors) | Aug 2–16 (sowing) |
| Sunflower | – | Jun 10–24 (sow outdoors) | – |
| Asparagus (crowns) | – | May 13–27 (transplant) | – |
| Rhubarb (crowns) | – | May 13–27 (transplant) | – |
| Strawberry (plants) | – | May 13–27 (transplant) | Jul 19–Aug 16 (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: Mund's Park, AZ (NOAA GHCN-Daily ID USC00025780), elevation 6,470 ft, 8.7 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Happy Jack Rs, AZ | 12 mi | Jun 1 | Oct 3 |
| Oak Creek Canyon, AZ | 15 mi | Apr 14 | Nov 5 |
| Sedona, AZ | 16 mi | Apr 1 | Nov 17 |
The average last-frost dates of these stations span 71 days, a rough guide to local variation. See data sources & methods.
Frost questions for 86038
When is the last frost in 86038?
The average (50% chance) last spring freeze of 32°F for ZIP 86038 is June 10. For a more cautious planting date, use June 27, when only 1 year in 10 still sees a later freeze.
When is the first frost in 86038?
The average first fall freeze is September 27. In 1 year in 10 it comes by September 14.
What hardiness zone is 86038?
ZIP 86038 is in USDA zone 6b (-5 to 0°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 86038 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
86017 Munds Park 86005 Flagstaff 86351 Village of Oak Creek (Big Park) 86335 Lake Montezuma 86336 Oak Creek Canyon 86011 Flagstaff 86024 Blue Ridge 86325 Cornville
Other ZIP codes in Coconino County
85931 86001 86003 86004 86005 86011 86015 86016 86017 86018 86020 86022 86023 86024 86030 86035 86036 86040 86044 86045 86046 86052 86053 86320 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.
- Freeze alerts
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- Weekly yard to-dos
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.