Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 50168 — Mingo, IA

ZIP code 50168 (Mingo, Jasper County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is April 22 and the first fall frost October 17.

Where ZIP 50168 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone5b−15 to −10 °F
Coldest night−26.1 to −23.3 °C
Last frostApr 22
First frostOct 17
2012 zone5a

Was 5a on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 5b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Mingo, IA…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in Mingo, IA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 22median — 50% chance of a later frost
Safe for tender plantsMay 4only 10% chance of frost after
First fall frostOctober 17median — 10% chance by Oct 1
Growing season174 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 12 and returns around October 26.

From the NOAA station Newton, IA — 14 miles away, elevation 961 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 50168

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 11 – Mar 25
SpinachSow outdoors · Mar 11 – Apr 1
Broccoli, cabbageStart indoors · Feb 11 – Feb 25
Broccoli, cabbageTransplant · Apr 1 – Apr 15
Onion setsPlant outdoors · Mar 25 – Apr 8
PotatoesPlant outdoors · Apr 1 – Apr 15
LettuceSow outdoors · Mar 25 – Apr 8
Carrots, beetsSow outdoors · Apr 1 – Apr 15
TomatoesStart indoors · Feb 25 – Mar 11
TomatoesTransplant · Apr 29 – May 13
Peppers, eggplantStart indoors · Feb 11 – Feb 25
Peppers, eggplantTransplant · May 6 – May 20
BeansSow outdoors · Apr 29 – May 13
Sweet cornSow outdoors · Apr 29 – May 13
Cucumbers, squashSow outdoors · Apr 29 – May 13
Fall lettuce, spinachSow outdoors · Aug 22 – Sep 5
GarlicPlant cloves · Oct 3 – Nov 7
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 22) and first fall frost (Oct 17) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 50168 came on Mar 23 — 12 days earlier than the 1991–2020 average (Apr 4).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Soil in Mingo, IA

The soil mapped at the center of ZIP 50168 is Clarion — loam, well drained.

TextureLoama good balance for most vegetables
pH6.2slightly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2.5%moderate
Hydrologic groupBwater soaks in moderately
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Clarion loam, Bemis moraine, 6 to 10 percent slopes, moderately eroded.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 50168; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mingo, IA

Summer high85 °Faverage high, July
Winter low10 °Faverage low, January
Hot days21days a year at 90 °F or more
Freezing nights142nights a year at 32 °F or less
Growing degree days3,112base 50 °F — the season’s usable heat
Longest day15 h 13 mindaylight on June 21
Shortest day9 h 08 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation35.1 inper year, rain and melted snow
Snowfall29 inper year

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 28 °F, low 10 °F 28°10° JanFebruary: average high 33 °F, low 14 °F 33°14° FebMarch: average high 46 °F, low 26 °F 46°26° MarApril: average high 60 °F, low 37 °F 60°37° AprMay: average high 71 °F, low 50 °F 71°50° MayJune: average high 81 °F, low 60 °F 81°60° JunJuly: average high 85 °F, low 64 °F 85°64° JulAugust: average high 83 °F, low 61 °F 83°61° AugSeptember: average high 76 °F, low 52 °F 76°52° SepOctober: average high 63 °F, low 40 °F 63°40° OctNovember: average high 47 °F, low 27 °F 47°27° NovDecember: average high 34 °F, low 17 °F 34°17° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″6″January: 0.93 in precipitation, 9.2 in snowfall 0.9❄9 JanFebruary: 1.10 in precipitation, 6 in snowfall 1.1❄6 FebMarch: 2.06 in precipitation, 4.5 in snowfall 2.1❄5 MarApril: 3.44 in precipitation, 0.8 in snowfall 3.4❄1 AprMay: 4.84 in precipitation 4.8 MayJune: 5.01 in precipitation 5.0 JunJuly: 3.93 in precipitation 3.9 JulAugust: 4.30 in precipitation 4.3 AugSeptember: 3.59 in precipitation 3.6 SepOctober: 2.66 in precipitation, 0.3 in snowfall 2.7 OctNovember: 2.01 in precipitation, 1.6 in snowfall 2.0❄2 NovDecember: 1.27 in precipitation, 6.3 in snowfall 1.3❄6 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Newton, IA (14 mi away); precipitation: Newton, IA (14 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 5b.

501275b
Ira, IA · 3 mi
500285b
Baxter, IA · 7 mi
500555b
Collins, IA · 7 mi
501615b
Maxwell, IA · 7 mi
500545b
Colfax, IA · 7 mi
502345b
Rhodes, IA · 9 mi
501695b
Mitchellville, IA · 10 mi
500355b
Bondurant, IA · 10 mi

Iowa planting zones →

Questions about 50168

What planting zone is ZIP code 50168?

ZIP code 50168 (Mingo, IA) is in USDA hardiness zone 5b on the 2023 map: the coldest night of an average winter reaches −15 to −10 °F (−26.1 to −23.3 °C).

When is the last frost in Mingo, IA?

The median last spring frost (32 °F) near 50168 is April 22; after May 4 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Newton station.

When is the first frost in Mingo, IA?

The median first fall frost near 50168 is October 17, giving a median frost-free growing season of 174 days.

When should I plant tomatoes in 50168?

Start tomato seeds indoors around Feb 25 – Mar 11 and set transplants outside around Apr 29 – May 13, one to three weeks after the median last frost.

How much rain and snow does 50168 get?

About 35.1 inches of precipitation a year and 29 inches of snowfall (NOAA 1991–2020 normals, Newton station).

How hot do summers get in Mingo, IA?

The average high peaks at 85 °F in July, with about 21 days a year at 90 °F or more.

What kind of soil does 50168 have?

The USDA soil survey maps Clarion at the center of ZIP 50168: loam, well drained, pH about 6.2 (slightly acidic).

Did spring come early in Mingo, IA in 2026?

Spring leaf-out near 50168 came on Mar 23 in 2026, 12 days earlier than the 1991–2020 average (Apr 4), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mingo, IA?

Long-day onions: the longest day near 50168 is 15 h 13 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 50168 change?

Yes. The 2012 USDA map put 50168 in zone 5a; the 2023 map puts it in zone 5b. The newer map uses 1991–2020 data and more weather stations.