Frost dates for ZIP 84780 (Washington, 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, St George, UT (7 miles away).
- Average last spring frostMar 1450% chance of a 32°F freeze after this date
- Average first fall frostNov 1050% chance of a 32°F freeze by this date
- Growing season (frost-free)239 daysmedian, 32°F threshold
- USDA hardiness zone8b15 to 20°F avg. coldest night
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This week in your yard
As of Oct 17, 2026, from your frost dates, zone and soil temperature. Lawn timing · Vegetables · Pruning · Plants
Soil temperature now
2-inch depth
64°F 55°F or warmer
24-hour average · latest 65°F, as of Oct 17, 10:00 PM CDT
Measured at USDA NRCS SCAN station Sand Hollow, 7 mi away. Daily averages: Thu 59°, Fri 62°.
4-inch depth
63°F 55°F or warmer
24-hour average · latest 66°F, as of Oct 17, 10:00 PM CDT
Measured at USDA NRCS SCAN station Sand Hollow, 7 mi away. Daily averages: Thu 58°, Fri 61°.
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 84780 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 63°F at 4 inches. Fall pre-emergent (annual bluegrass, winter weeds): window open as soil cools through the 70s and 60s.
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
Prune now
No frost-timed pruning windows are open this week.
Your average first frost is Nov 10: 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) | Feb 27 |
| 50% (the "average" last frost) | Mar 14 |
| 10% (cautious: only 1 year in 10 freezes later) | Apr 6 |
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 27 |
| 50% (the "average" first frost) | Nov 10 |
| 90% (late: most years have frozen by now) | Nov 22 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | Apr 3 | Nov 1 |
| 32°F (freeze) | Mar 14 | Nov 10 |
| 28°F (hard freeze) | Feb 27 | Nov 20 |
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 84780
Dates count from your average last spring frost (Mar 14) and first fall frost (Nov 10). 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 | Jan 17–31 | Mar 21–Apr 4 (transplant) | Jul 14–Aug 11 (transplant) |
| Pepper (sweet and hot) | Jan 3–17 | Mar 28–Apr 11 (transplant) | Jul 21–Aug 11 (transplant) |
| Eggplant | Jan 3–17 | Mar 28–Apr 11 (transplant) | Jul 21–Aug 11 (transplant) |
| Tomatillo | Jan 17–31 | Mar 21–Apr 4 (transplant) | – |
| Lettuce | Jan 17–31 | Feb 21–Mar 14 (transplant) Feb 14–Mar 28 (sow outdoors) | Sep 15–Oct 6 (transplant) Sep 1–29 (sowing) |
| Spinach | – | Jan 31–Feb 21 (sow outdoors) | Sep 15–Oct 6 (sowing) |
| Kale | Jan 17–31 | Feb 14–28 (transplant) Feb 14–28 (sow outdoors) | Aug 18–Sep 15 (transplant) Aug 4–Sep 1 (sowing) |
| Collards | Jan 17–31 | Feb 14–Mar 14 (transplant) Feb 14–Mar 14 (sow outdoors) | Aug 18–Sep 15 (transplant) Aug 4–Sep 1 (sowing) |
| Broccoli | Jan 3–17 | Feb 14–28 (transplant) | Aug 4–Sep 1 (transplant) |
| Cabbage | Jan 3–17 | Feb 14–28 (transplant) | Aug 4–Sep 1 (transplant) |
| Cauliflower | Jan 3–17 | Feb 28–Mar 14 (transplant) | Aug 4–Sep 1 (transplant) |
| Brussels sprouts | Dec 20–Jan 3 | Feb 14–28 (transplant) | Jul 21–Aug 11 (transplant) |
| Kohlrabi | Jan 17–31 | Feb 14–28 (transplant) Feb 14–28 (sow outdoors) | Sep 1–15 (sowing) |
| Bok choy / Asian greens | – | Feb 14–28 (sow outdoors) | Sep 15–29 (sowing) |
| Arugula | – | Feb 14–Mar 14 (sow outdoors) | Sep 15–Oct 13 (sowing) |
| Mustard greens | – | Feb 14–Mar 7 (sow outdoors) | Sep 15–29 (sowing) |
| Swiss chard | Jan 31–Feb 14 | Feb 28–Mar 21 (transplant) Feb 28–Mar 28 (sow outdoors) | Sep 1–15 (sowing) |
| Beet | – | Feb 14–Mar 14 (sow outdoors) | Sep 1–15 (sowing) |
| Carrot | – | Feb 21–Mar 21 (sow outdoors) | Aug 18–Sep 1 (sowing) |
| Radish | – | Feb 7–Mar 21 (sow outdoors) | Sep 29–Oct 13 (sowing) |
| Turnip | – | Feb 14–Mar 7 (sow outdoors) | Sep 1–15 (sowing) |
| Parsnip | – | Feb 21–Mar 14 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Jan 17–Feb 14 (sow outdoors) | Aug 18–Sep 1 (sowing) |
| Onion (bulbing) | Dec 20–Jan 3 | Jan 31–Feb 14 (transplant) | – |
| Green onion / scallion | – | Jan 31–Feb 28 (sow outdoors) | Sep 1–15 (sowing) |
| Leek | Dec 20–Jan 3 | Feb 14–28 (transplant) | – |
| Garlic | – | – | Sep 29–Oct 27 (sowing) |
| Shallot | – | Jan 31–Feb 14 (transplant) | Sep 29–Oct 27 (sowing) |
| Potato | – | Feb 14–28 (transplant) | Jul 21–Aug 4 (transplant) |
| Sweet potato | – | Apr 4–18 (transplant) | – |
| Sweet corn | – | Mar 21–Apr 4 (sow outdoors) | – |
| Bean, bush (snap) | – | Mar 21–Apr 4 (sow outdoors) | Aug 18–Sep 1 (sowing) |
| Bean, pole | – | Mar 21–Apr 4 (sow outdoors) | – |
| Lima bean | – | Mar 28–Apr 11 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Apr 4–25 (sow outdoors) | – |
| Cucumber | Feb 14–21 | Mar 21–Apr 4 (transplant) Mar 21–Apr 4 (sow outdoors) | Aug 18–Sep 1 (sowing) |
| Summer squash / zucchini | Feb 14–21 | Mar 21–Apr 4 (transplant) Mar 21–Apr 4 (sow outdoors) | Aug 18–Sep 1 (sowing) |
| Winter squash | Feb 14–21 | Mar 21–Apr 4 (transplant) Mar 21–Apr 4 (sow outdoors) | – |
| Pumpkin | – | Mar 21–Apr 4 (sow outdoors) | – |
| Watermelon | Feb 14–21 | Mar 28–Apr 11 (transplant) Mar 28–Apr 11 (sow outdoors) | – |
| Cantaloupe / muskmelon | Feb 14–21 | Mar 28–Apr 11 (transplant) Mar 28–Apr 11 (sow outdoors) | – |
| Okra | Jan 31–Feb 14 | Mar 28–Apr 11 (transplant) Mar 28–Apr 11 (sow outdoors) | – |
| Celery | Dec 20–Jan 3 | Mar 21–28 (transplant) | – |
| Basil | Jan 31–Feb 14 | Mar 21–Apr 4 (transplant) Mar 21–Apr 4 (sow outdoors) | – |
| Cilantro | – | Feb 28–Mar 28 (sow outdoors) | Sep 15–29 (sowing) |
| Parsley | Jan 3–17 | Feb 28–Mar 14 (transplant) Feb 21–Mar 14 (sow outdoors) | – |
| Dill | – | Mar 14–28 (sow outdoors) | Sep 15–29 (sowing) |
| Sunflower | – | Mar 14–28 (sow outdoors) | – |
| Asparagus (crowns) | – | Feb 14–28 (transplant) | – |
| Rhubarb (crowns) | – | Feb 14–28 (transplant) | – |
| Strawberry (plants) | – | Feb 14–28 (transplant) | Sep 1–29 (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: St George, UT (NOAA GHCN-Daily ID USC00427516), elevation 2,857 ft, 7.4 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| La Verkin, UT | 12 mi | Apr 1 | Nov 5 |
| Veyo Powerhouse, UT | 19 mi | Apr 9 | Nov 5 |
| New Harmony, UT | 25 mi | May 9 | Oct 11 |
The average last-frost dates of these stations span 57 days, a rough guide to local variation. See data sources & methods.
Frost questions for 84780
When is the last frost in 84780?
The average (50% chance) last spring freeze of 32°F for ZIP 84780 is March 14. For a more cautious planting date, use April 6, when only 1 year in 10 still sees a later freeze.
When is the first frost in 84780?
The average first fall freeze is November 10. In 1 year in 10 it comes by October 27.
What hardiness zone is 84780?
ZIP 84780 is in USDA zone 8b (15 to 20°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 84780 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
84790 St. George 84770 St. George 84746 Leeds 84745 La Verkin 84774 Toquerville 84738 Ivins 84737 Hurricane 84783 Dammeron Valley
Other ZIP codes in Washington County
84722 84725 84733 84737 84738 84745 84746 84757 84763 84765 84767 84770 84774 84779 84781 84782 84783 84784 84790 All Washington County frost dates · Utah frost dates
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