Fall in zone 6bPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 84520 (East Carbon, UT)
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, Sunnyside City Ctr, UT (2 miles away).
- Average last spring frostMay 550% chance of a 32°F freeze after this date
- Average first fall frostOct 1550% chance of a 32°F freeze by this date
- Growing season (frost-free)159 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
52°F 50–55°F
24-hour average · latest 49°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Price (21 mi), Green River (38 mi), Little Red Fox (45 mi).
4-inch depth
52°F 50–55°F
24-hour average · latest 51°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Price (21 mi), Green River (38 mi), Little Red Fox (45 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 84520 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 52°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.
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 21 |
| 50% (the "average" last frost) | May 5 |
| 10% (cautious: only 1 year in 10 freezes later) | May 26 |
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 30 |
| 50% (the "average" first frost) | Oct 15 |
| 90% (late: most years have frozen by now) | Nov 1 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | May 22 | Oct 2 |
| 32°F (freeze) | May 5 | Oct 15 |
| 28°F (hard freeze) | Apr 24 | Oct 25 |
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 84520
Dates count from your average last spring frost (May 5) and first fall frost (Oct 15). 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 10–24 | May 12–26 (transplant) | – |
| Pepper (sweet and hot) | Feb 24–Mar 10 | May 19–Jun 2 (transplant) | – |
| Eggplant | Feb 24–Mar 10 | May 19–Jun 2 (transplant) | – |
| Tomatillo | Mar 10–24 | May 12–26 (transplant) | – |
| Lettuce | Mar 10–24 | Apr 14–May 5 (transplant) Apr 7–May 19 (sow outdoors) | Aug 20–Sep 10 (transplant) Aug 6–Sep 3 (sowing) |
| Spinach | – | Mar 24–Apr 14 (sow outdoors) | Aug 20–Sep 10 (sowing) |
| Kale | Mar 10–24 | Apr 7–21 (transplant) Apr 7–21 (sow outdoors) | Jul 23–Aug 20 (transplant) Jul 9–Aug 6 (sowing) |
| Collards | Mar 10–24 | Apr 7–May 5 (transplant) Apr 7–May 5 (sow outdoors) | Jul 23–Aug 20 (transplant) Jul 9–Aug 6 (sowing) |
| Broccoli | Feb 24–Mar 10 | Apr 7–21 (transplant) | Jul 9–Aug 6 (transplant) |
| Cabbage | Feb 24–Mar 10 | Apr 7–21 (transplant) | Jul 9–Aug 6 (transplant) |
| Cauliflower | Feb 24–Mar 10 | Apr 21–May 5 (transplant) | Jul 9–Aug 6 (transplant) |
| Brussels sprouts | Feb 10–24 | Apr 7–21 (transplant) | Jun 25–Jul 16 (transplant) |
| Kohlrabi | Mar 10–24 | Apr 7–21 (transplant) Apr 7–21 (sow outdoors) | Aug 6–20 (sowing) |
| Bok choy / Asian greens | – | Apr 7–21 (sow outdoors) | Aug 20–Sep 3 (sowing) |
| Arugula | – | Apr 7–May 5 (sow outdoors) | Aug 20–Sep 17 (sowing) |
| Mustard greens | – | Apr 7–28 (sow outdoors) | Aug 20–Sep 3 (sowing) |
| Swiss chard | Mar 24–Apr 7 | Apr 21–May 12 (transplant) Apr 21–May 19 (sow outdoors) | Aug 6–20 (sowing) |
| Beet | – | Apr 7–May 5 (sow outdoors) | Aug 6–20 (sowing) |
| Carrot | – | Apr 14–May 12 (sow outdoors) | Jul 23–Aug 6 (sowing) |
| Radish | – | Mar 31–May 12 (sow outdoors) | Sep 3–17 (sowing) |
| Turnip | – | Apr 7–28 (sow outdoors) | Aug 6–20 (sowing) |
| Parsnip | – | Apr 14–May 5 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Mar 10–Apr 7 (sow outdoors) | Jul 23–Aug 6 (sowing) |
| Onion (bulbing) | Feb 10–24 | Mar 24–Apr 7 (transplant) | – |
| Green onion / scallion | – | Mar 24–Apr 21 (sow outdoors) | Aug 6–20 (sowing) |
| Leek | Feb 10–24 | Apr 7–21 (transplant) | – |
| Garlic | – | – | Sep 3–Oct 1 (sowing) |
| Shallot | – | Mar 24–Apr 7 (transplant) | Sep 3–Oct 1 (sowing) |
| Potato | – | Apr 7–21 (transplant) | Jun 25–Jul 9 (transplant) |
| Sweet potato | – | May 26–Jun 9 (transplant) | – |
| Sweet corn | – | May 12–26 (sow outdoors) | – |
| Bean, bush (snap) | – | May 12–26 (sow outdoors) | – |
| Bean, pole | – | May 12–26 (sow outdoors) | – |
| Lima bean | – | May 19–Jun 2 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 26–Jun 16 (sow outdoors) | – |
| Cucumber | Apr 7–14 | May 12–26 (transplant) May 12–26 (sow outdoors) | – |
| Summer squash / zucchini | Apr 7–14 | May 12–26 (transplant) May 12–26 (sow outdoors) | – |
| Winter squash | Apr 7–14 | May 12–26 (transplant) May 12–26 (sow outdoors) | – |
| Pumpkin | – | May 12–26 (sow outdoors) | – |
| Watermelon | Apr 7–14 | May 19–Jun 2 (transplant) May 19–Jun 2 (sow outdoors) | – |
| Cantaloupe / muskmelon | Apr 7–14 | May 19–Jun 2 (transplant) May 19–Jun 2 (sow outdoors) | – |
| Okra | Mar 24–Apr 7 | May 19–Jun 2 (transplant) May 19–Jun 2 (sow outdoors) | – |
| Celery | Feb 10–24 | May 12–19 (transplant) | – |
| Basil | Mar 24–Apr 7 | May 12–26 (transplant) May 12–26 (sow outdoors) | – |
| Cilantro | – | Apr 21–May 19 (sow outdoors) | Aug 20–Sep 3 (sowing) |
| Parsley | Feb 24–Mar 10 | Apr 21–May 5 (transplant) Apr 14–May 5 (sow outdoors) | – |
| Dill | – | May 5–19 (sow outdoors) | Aug 20–Sep 3 (sowing) |
| Sunflower | – | May 5–19 (sow outdoors) | – |
| Asparagus (crowns) | – | Apr 7–21 (transplant) | – |
| Rhubarb (crowns) | – | Apr 7–21 (transplant) | – |
| Strawberry (plants) | – | Apr 7–21 (transplant) | Aug 6–Sep 3 (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: Sunnyside City Ctr, UT (NOAA GHCN-Daily ID USC00428478), elevation 6,530 ft, 2.3 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Sunnyside City, UT | 2 mi | Apr 26 | Oct 25 |
| Wellington 3 E, UT | 14 mi | May 27 | Sep 26 |
| Price Carbon Co AP, UT | 19 mi | May 3 | Oct 12 |
The average last-frost dates of these stations span 32 days, a rough guide to local variation. See data sources & methods.
Frost questions for 84520
When is the last frost in 84520?
The average (50% chance) last spring freeze of 32°F for ZIP 84520 is May 5. For a more cautious planting date, use May 26, when only 1 year in 10 still sees a later freeze.
When is the first frost in 84520?
The average first fall freeze is October 15. In 1 year in 10 it comes by September 30.
What hardiness zone is 84520?
ZIP 84520 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 84520 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
84539 East Carbon 84542 Wellington 84521 Elmo 84501 Price 84529 Kenilworth 84518 Cleveland 84526 Spring Glen 84525 Green River
Other ZIP codes in Carbon County
84501 84526 84529 84539 84542 All Carbon County frost dates · Utah frost dates
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Weekly yard timing, plus frost and soil-temperature alerts for your ZIP code.
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