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Frost dates for ZIP 50532 (Duncombe, IA)

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, Webster City, IA (10 miles away).

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

53°F 50–55°F
24-hour average · latest 54°F, as of Oct 18, 2:00 AM CDT

30°50°55°70°90°

Estimate Not a measurement at this ZIP: distance-weighted average of Ames (34 mi).

4-inch depth

55°F 50–55°F
24-hour average · latest 55°F, as of Oct 18, 2:00 AM CDT

30°50°55°70°90°

Estimate Not a measurement at this ZIP: distance-weighted average of Ames (34 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 50532 load here. You can also open the NWS forecast for this ZIP.

Pre-emergent

Soil is 55°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 early May).

Fertilizer window

Lawn region: North (cool-season). 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.

JanFebMarAprMayJunJulAugSepOctNovDecLight blue: spring freeze risk (90% to 10%). Tan: fall freeze risk (10% to 90%). Dark lines: 50% dates.

Last spring frost odds

Chance of a 32°F freeze after this dateDate
90% (early: most years still freeze after this)Apr 20
50% (the "average" last frost)May 3
10% (cautious: only 1 year in 10 freezes later)May 16

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 dateDate
10% (early: 1 year in 10 freezes this soon)Sep 18
50% (the "average" first frost)Oct 2
90% (late: most years have frozen by now)Oct 16

Light frost, freeze and hard freeze

ThresholdLast spring (50%)First fall (50%)
36°F (light frost possible on clear, calm nights)May 11Sep 23
32°F (freeze)May 3Oct 2
28°F (hard freeze)Apr 24Oct 12

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 50532

Dates count from your average last spring frost (May 3) and first fall frost (Oct 2). Half of years have a frost after the spring date, so give tender crops (tomatoes, peppers, squash) some slack.

Start seeds indoorsSpring plantingFall plantingLast frostFirst frostJanFebMarAprMayJunJulAugSepOctNovDecTomatoPepperEggplantTomatilloLettuceSpinachKaleCollardsBroccoliCabbageCauliflowerBrussels sproutsKohlrabiBok choy / Asian greensArugulaMustard greensSwiss chardBeetCarrotRadishTurnipParsnipPeaOnionGreen onion / scallionLeekGarlicShallotPotatoSweet potatoSweet cornBean, bushBean, poleLima beanSouthern peaCucumberSummer squash / zucchiniWinter squashPumpkinWatermelonCantaloupe / muskmelonOkraCeleryBasilCilantroParsleyDillSunflowerAsparagusRhubarbStrawberry
CropStart indoorsSpring plantingFall planting
TomatoMar 8–22May 10–24 (transplant)–
Pepper (sweet and hot)Feb 22–Mar 8May 17–31 (transplant)–
EggplantFeb 22–Mar 8May 17–31 (transplant)–
TomatilloMar 8–22May 10–24 (transplant)–
LettuceMar 8–22Apr 12–May 3 (transplant)
Apr 5–May 17 (sow outdoors)
Aug 7–28 (transplant)
Jul 24–Aug 21 (sowing)
Spinach–Mar 22–Apr 12 (sow outdoors)Aug 7–28 (sowing)
KaleMar 8–22Apr 5–19 (transplant)
Apr 5–19 (sow outdoors)
Jul 10–Aug 7 (transplant)
Jun 26–Jul 24 (sowing)
CollardsMar 8–22Apr 5–May 3 (transplant)
Apr 5–May 3 (sow outdoors)
Jul 10–Aug 7 (transplant)
Jun 26–Jul 24 (sowing)
BroccoliFeb 22–Mar 8Apr 5–19 (transplant)Jun 26–Jul 24 (transplant)
CabbageFeb 22–Mar 8Apr 5–19 (transplant)Jun 26–Jul 24 (transplant)
CauliflowerFeb 22–Mar 8Apr 19–May 3 (transplant)Jun 26–Jul 24 (transplant)
Brussels sproutsFeb 8–22Apr 5–19 (transplant)Jun 12–Jul 3 (transplant)
KohlrabiMar 8–22Apr 5–19 (transplant)
Apr 5–19 (sow outdoors)
Jul 24–Aug 7 (sowing)
Bok choy / Asian greens–Apr 5–19 (sow outdoors)Aug 7–21 (sowing)
Arugula–Apr 5–May 3 (sow outdoors)Aug 7–Sep 4 (sowing)
Mustard greens–Apr 5–26 (sow outdoors)Aug 7–21 (sowing)
Swiss chardMar 22–Apr 5Apr 19–May 10 (transplant)
Apr 19–May 17 (sow outdoors)
Jul 24–Aug 7 (sowing)
Beet–Apr 5–May 3 (sow outdoors)Jul 24–Aug 7 (sowing)
Carrot–Apr 12–May 10 (sow outdoors)Jul 10–24 (sowing)
Radish–Mar 29–May 10 (sow outdoors)Aug 21–Sep 4 (sowing)
Turnip–Apr 5–26 (sow outdoors)Jul 24–Aug 7 (sowing)
Parsnip–Apr 12–May 3 (sow outdoors)–
Pea (garden, snap, snow)–Mar 8–Apr 5 (sow outdoors)Jul 10–24 (sowing)
Onion (bulbing)Feb 8–22Mar 22–Apr 5 (transplant)–
Green onion / scallion–Mar 22–Apr 19 (sow outdoors)Jul 24–Aug 7 (sowing)
LeekFeb 8–22Apr 5–19 (transplant)–
Garlic––Aug 21–Sep 18 (sowing)
Shallot–Mar 22–Apr 5 (transplant)Aug 21–Sep 18 (sowing)
Potato–Apr 5–19 (transplant)Jun 12–26 (transplant)
Sweet potato–May 24–Jun 7 (transplant)–
Sweet corn–May 10–24 (sow outdoors)–
Bean, bush (snap)–May 10–24 (sow outdoors)–
Bean, pole–May 10–24 (sow outdoors)–
Lima bean–May 17–31 (sow outdoors)–
Southern pea (cowpea, black-eyed pea)–May 24–Jun 14 (sow outdoors)–
CucumberApr 5–12May 10–24 (transplant)
May 10–24 (sow outdoors)
–
Summer squash / zucchiniApr 5–12May 10–24 (transplant)
May 10–24 (sow outdoors)
–
Winter squashApr 5–12May 10–24 (transplant)
May 10–24 (sow outdoors)
–
Pumpkin–May 10–24 (sow outdoors)–
WatermelonApr 5–12May 17–31 (transplant)
May 17–31 (sow outdoors)
–
Cantaloupe / muskmelonApr 5–12May 17–31 (transplant)
May 17–31 (sow outdoors)
–
OkraMar 22–Apr 5May 17–31 (transplant)
May 17–31 (sow outdoors)
–
CeleryFeb 8–22May 10–17 (transplant)–
BasilMar 22–Apr 5May 10–24 (transplant)
May 10–24 (sow outdoors)
–
Cilantro–Apr 19–May 17 (sow outdoors)Aug 7–21 (sowing)
ParsleyFeb 22–Mar 8Apr 19–May 3 (transplant)
Apr 12–May 3 (sow outdoors)
–
Dill–May 3–17 (sow outdoors)Aug 7–21 (sowing)
Sunflower–May 3–17 (sow outdoors)–
Asparagus (crowns)–Apr 5–19 (transplant)–
Rhubarb (crowns)–Apr 5–19 (transplant)–
Strawberry (plants)–Apr 5–19 (transplant)Jul 24–Aug 21 (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: Webster City, IA (NOAA GHCN-Daily ID USC00138806), elevation 1,072 ft, 10.4 miles from the ZIP's center point. NOAA completeness flag: S (standard, 24+ years).

Nearby stations

StationDistanceLast frost (50%)First frost (50%)
Ft Dodge 5NNW, IA13 miApr 28Oct 8
Dakota City, IA21 miApr 26Oct 12
Humboldt WTP, IA21 miApr 27Oct 9

The average last-frost dates of these stations span 8 days, a rough guide to local variation. See data sources & methods.

Frost questions for 50532

When is the last frost in 50532?

The average (50% chance) last spring freeze of 32°F for ZIP 50532 is May 3. For a more cautious planting date, use May 16, when only 1 year in 10 still sees a later freeze.

When is the first frost in 50532?

The average first fall freeze is October 2. In 1 year in 10 it comes by September 18.

What hardiness zone is 50532?

ZIP 50532 is in USDA zone 5a (-20 to -15°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.

What is the soil temperature in 50532 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

50557 Lehigh 50569 Otho 50594 Vincent 50595 Webster City 50521 50501 Fort Dodge 50599 Woolstock 50516 Badger

Other ZIP codes in Webster County

50501 50516 50518 50521 50523 50524 50530 50543 50544 50557 50566 50569 50594 All Webster County frost dates · Iowa frost dates