Fall in zone 9aPhoto: George Chernilevsky, Public domain, via Wikimedia Commons
Frost dates for ZIP 85145 (Red Rock, 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, Picacho 8 SE, AZ (7 miles away).
- Average last spring frostFeb 650% chance of a 32°F freeze after this date
- Average first fall frostDec 950% chance of a 32°F freeze by this date
- Growing season (frost-free)308 daysmedian, 32°F threshold
- USDA hardiness zone9a20 to 25°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
76°F 55°F or warmer
24-hour average · latest 73°F, as of Oct 18, 1:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Tucson 11 W (24 mi).
4-inch depth
76°F 55°F or warmer
24-hour average · latest 75°F, as of Oct 18, 1:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Tucson 11 W (24 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 85145 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 76°F at 4 inches (estimated soil temperature, not a station reading). Fall pre-emergent (annual bluegrass, winter weeds): not yet. Apply as soil cools toward 70°F (typically September to October).
Fertilizer window
Lawn region: Arid Southwest (low desert). Timing only; always follow the product label.
- Bermudagrass (warm-season): Spring: Several weeks after the lawn is fully green (April–May) (about Mar 24 here, using green-up about 3–4 weeks after your average last frost); Summer: Every 4–6 weeks through mid-August (heaviest feeder of the group); Late: Light, low-nitrogen/high-potassium feeding about 4 weeks before first frost, or skip. Avoid: Heavy late-fall nitrogen (linked to spring dead spot).
- Perennial ryegrass (cool-season): Early fall: September; Late fall: October–November; Overseeded Bermuda: Light feeding once the winter rye is established, if needed. Avoid: Summer feeding.
Plant now
- Lettuce: fall sowing Sep 30–Oct 28
- Lettuce: fall transplant Oct 14–Nov 4
- Spinach: fall sowing Oct 14–Nov 4
- Bok choy / Asian greens: fall sowing Oct 14–28
- Arugula: fall sowing Oct 14–Nov 11
- Mustard greens: fall sowing Oct 14–28
- Cilantro: fall sowing Oct 14–28
- Dill: fall sowing Oct 14–28
- Strawberry (plants): fall transplant Sep 30–Oct 28
Coming up in the next 3 weeks
- Radish: fall sowing Oct 28–Nov 11
- Garlic: fall sowing Oct 28–Nov 25
- Shallot: fall sowing Oct 28–Nov 25
Prune now
No frost-timed pruning windows are open this week.
Your average first frost is Dec 9: 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) | Jan 6 |
| 50% (the "average" last frost) | Feb 6 |
| 10% (cautious: only 1 year in 10 freezes later) | Mar 5 |
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) | Nov 22 |
| 50% (the "average" first frost) | Dec 9 |
| 90% (late: most years have frozen by now) | Dec 26 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | Feb 28 | Nov 29 |
| 32°F (freeze) | Feb 6 | Dec 9 |
| 28°F (hard freeze) | Jan 14 | Dec 19 |
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 85145
Dates count from your average last spring frost (Feb 6) and first fall frost (Dec 9). 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 | Dec 12–26 | Feb 13–27 (transplant) | Aug 12–Sep 9 (transplant) |
| Pepper (sweet and hot) | Nov 28–Dec 12 | Feb 20–Mar 6 (transplant) | Aug 19–Sep 9 (transplant) |
| Eggplant | Nov 28–Dec 12 | Feb 20–Mar 6 (transplant) | Aug 19–Sep 9 (transplant) |
| Tomatillo | Dec 12–26 | Feb 13–27 (transplant) | – |
| Lettuce | Dec 12–26 | Jan 16–Feb 6 (transplant) Jan 9–Feb 20 (sow outdoors) | Oct 14–Nov 4 (transplant) Sep 30–Oct 28 (sowing) |
| Spinach | – | Dec 26–Jan 16 (sow outdoors) | Oct 14–Nov 4 (sowing) |
| Kale | Dec 12–26 | Jan 9–23 (transplant) Jan 9–23 (sow outdoors) | Sep 16–Oct 14 (transplant) Sep 2–30 (sowing) |
| Collards | Dec 12–26 | Jan 9–Feb 6 (transplant) Jan 9–Feb 6 (sow outdoors) | Sep 16–Oct 14 (transplant) Sep 2–30 (sowing) |
| Broccoli | Nov 28–Dec 12 | Jan 9–23 (transplant) | Sep 2–30 (transplant) |
| Cabbage | Nov 28–Dec 12 | Jan 9–23 (transplant) | Sep 2–30 (transplant) |
| Cauliflower | Nov 28–Dec 12 | Jan 23–Feb 6 (transplant) | Sep 2–30 (transplant) |
| Brussels sprouts | Nov 14–28 | Jan 9–23 (transplant) | Aug 19–Sep 9 (transplant) |
| Kohlrabi | Dec 12–26 | Jan 9–23 (transplant) Jan 9–23 (sow outdoors) | Sep 30–Oct 14 (sowing) |
| Bok choy / Asian greens | – | Jan 9–23 (sow outdoors) | Oct 14–28 (sowing) |
| Arugula | – | Jan 9–Feb 6 (sow outdoors) | Oct 14–Nov 11 (sowing) |
| Mustard greens | – | Jan 9–30 (sow outdoors) | Oct 14–28 (sowing) |
| Swiss chard | Dec 26–Jan 9 | Jan 23–Feb 13 (transplant) Jan 23–Feb 20 (sow outdoors) | Sep 30–Oct 14 (sowing) |
| Beet | – | Jan 9–Feb 6 (sow outdoors) | Sep 30–Oct 14 (sowing) |
| Carrot | – | Jan 16–Feb 13 (sow outdoors) | Sep 16–30 (sowing) |
| Radish | – | Jan 2–Feb 13 (sow outdoors) | Oct 28–Nov 11 (sowing) |
| Turnip | – | Jan 9–30 (sow outdoors) | Sep 30–Oct 14 (sowing) |
| Parsnip | – | Jan 16–Feb 6 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Dec 12–Jan 9 (sow outdoors) | Sep 16–30 (sowing) |
| Onion (bulbing) | Nov 14–28 | Dec 26–Jan 9 (transplant) | – |
| Green onion / scallion | – | Dec 26–Jan 23 (sow outdoors) | Sep 30–Oct 14 (sowing) |
| Leek | Nov 14–28 | Jan 9–23 (transplant) | – |
| Garlic | – | – | Oct 28–Nov 25 (sowing) |
| Shallot | – | Dec 26–Jan 9 (transplant) | Oct 28–Nov 25 (sowing) |
| Potato | – | Jan 9–23 (transplant) | Aug 19–Sep 2 (transplant) |
| Sweet potato | – | Feb 27–Mar 13 (transplant) | – |
| Sweet corn | – | Feb 13–27 (sow outdoors) | – |
| Bean, bush (snap) | – | Feb 13–27 (sow outdoors) | Sep 16–30 (sowing) |
| Bean, pole | – | Feb 13–27 (sow outdoors) | – |
| Lima bean | – | Feb 20–Mar 6 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Feb 27–Mar 20 (sow outdoors) | – |
| Cucumber | Jan 9–16 | Feb 13–27 (transplant) Feb 13–27 (sow outdoors) | Sep 16–30 (sowing) |
| Summer squash / zucchini | Jan 9–16 | Feb 13–27 (transplant) Feb 13–27 (sow outdoors) | Sep 16–30 (sowing) |
| Winter squash | Jan 9–16 | Feb 13–27 (transplant) Feb 13–27 (sow outdoors) | – |
| Pumpkin | – | Feb 13–27 (sow outdoors) | – |
| Watermelon | Jan 9–16 | Feb 20–Mar 6 (transplant) Feb 20–Mar 6 (sow outdoors) | – |
| Cantaloupe / muskmelon | Jan 9–16 | Feb 20–Mar 6 (transplant) Feb 20–Mar 6 (sow outdoors) | – |
| Okra | Dec 26–Jan 9 | Feb 20–Mar 6 (transplant) Feb 20–Mar 6 (sow outdoors) | – |
| Celery | Nov 14–28 | Feb 13–20 (transplant) | – |
| Basil | Dec 26–Jan 9 | Feb 13–27 (transplant) Feb 13–27 (sow outdoors) | – |
| Cilantro | – | Jan 23–Feb 20 (sow outdoors) | Oct 14–28 (sowing) |
| Parsley | Nov 28–Dec 12 | Jan 23–Feb 6 (transplant) Jan 16–Feb 6 (sow outdoors) | – |
| Dill | – | Feb 6–20 (sow outdoors) | Oct 14–28 (sowing) |
| Sunflower | – | Feb 6–20 (sow outdoors) | – |
| Asparagus (crowns) | – | Jan 9–23 (transplant) | – |
| Rhubarb (crowns) | – | Jan 9–23 (transplant) | – |
| Strawberry (plants) | – | Jan 9–23 (transplant) | Sep 30–Oct 28 (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: Picacho 8 SE, AZ (NOAA GHCN-Daily ID USC00026513), elevation 1,981 ft, 7.3 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Eloy 4 NE, AZ | 18 mi | Feb 24 | Nov 28 |
| Arizona City, AZ | 22 mi | Feb 28 | Nov 21 |
| Tucson 17 NW, AZ | 23 mi | Feb 23 | Dec 6 |
The average last-frost dates of these stations span 22 days, a rough guide to local variation. See data sources & methods.
Frost questions for 85145
When is the last frost in 85145?
The average (50% chance) last spring freeze of 32°F for ZIP 85145 is February 6. For a more cautious planting date, use March 5, when only 1 year in 10 still sees a later freeze.
When is the first frost in 85145?
The average first fall freeze is December 9. In 1 year in 10 it comes by November 22.
What hardiness zone is 85145?
ZIP 85145 is in USDA zone 9a (20 to 25°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 85145 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
85141 Picacho 85653 Marana 85131 Eloy 85658 Marana 85654 Rillito 85123 Eloy 85743 Picture Rocks 85742 Casas Adobes
Other ZIP codes in Pinal County
85118 85119 85120 85121 85122 85123 85128 85131 85132 85137 85138 85139 85140 85141 85142 85143 85147 85172 85173 85191 85192 85193 85194 85618 All Pinal 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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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.