Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 52356 — Wellman, IA

ZIP code 52356 (Wellman, Washington County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is April 28 and the first fall frost October 11.

Where ZIP 52356 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 28

First frostOct 11

2012 zone5b

Same zone as on the 2012 map. 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 Wellman, 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 Wellman, IA

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostApril 28median — 50% chance of a later frost

Safe for tender plantsMay 11only 10% chance of frost after

First fall frostOctober 11median — 10% chance by Sep 25

Growing season165 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 17 and returns around October 22.

From the NOAA station Washington, IA — 15 miles away, elevation 686 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 52356

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 17 – Mar 31

SpinachSow outdoors · Mar 17 – Apr 7

Broccoli, cabbageStart indoors · Feb 17 – Mar 3

Broccoli, cabbageTransplant · Apr 7 – Apr 21

Onion setsPlant outdoors · Mar 31 – Apr 14

PotatoesPlant outdoors · Apr 7 – Apr 21

LettuceSow outdoors · Mar 31 – Apr 14

Carrots, beetsSow outdoors · Apr 7 – Apr 21

TomatoesStart indoors · Mar 3 – Mar 17

TomatoesTransplant · May 5 – May 19

Peppers, eggplantStart indoors · Feb 17 – Mar 3

Peppers, eggplantTransplant · May 12 – May 26

BeansSow outdoors · May 5 – May 19

Sweet cornSow outdoors · May 5 – May 19

Cucumbers, squashSow outdoors · May 5 – May 19

Fall lettuce, spinachSow outdoors · Aug 16 – Aug 30

GarlicPlant cloves · Sep 27 – Nov 1

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 28) and first fall frost (Oct 11) 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 52356 came on Mar 23 — 12 days earlier than the 1991–2020 average (Apr 4).

average
Apr 42026
Mar 23

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).

Native plants for zone 5b in Iowa

473 plants native to the lower 48 states, recorded in Iowa, and rated by the USDA to survive −15 °F or colder — the bottom of zone 5b. Each links to its USDA PLANTS profile.

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Wellman, IA.

Soil in Wellman, IA

The soil mapped at the center of ZIP 52356 is Ladoga — silt loam, moderately well drained.

TextureSilt loama good balance for most vegetables

pH6.6neutral; most vegetables like 6.0–7.0

DrainageModerately well drainednatural drainage class

Organic matter3%moderate

Hydrologic groupCwater soaks in slowly

Farmland classprime farmlandUSDA classification

Map unit: Ladoga silt loam, 2 to 5 percent slopes.

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 52356; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Wellman, IA

Summer high85 °Faverage high, July

Winter low12 °Faverage low, January

Hot days20days a year at 90 °F or more

Freezing nights140nights a year at 32 °F or less

Growing degree days3,155base 50 °F — the season’s usable heat

Longest day15 h 11 mindaylight on June 21

Shortest day9 h 10 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation38.1 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Washington, IA (15 mi away); precipitation: North English, IA (11 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 5b.

West Chester, IA · 9 mi

522485b

Keota, IA · 10 mi

523355b

South English, IA · 11 mi

522445b

Iowa City, IA · 12 mi

522315b

Harper, IA · 14 mi

523165b

North English, IA · 14 mi

Iowa planting zones →

Questions about 52356

What planting zone is ZIP code 52356?

ZIP code 52356 (Wellman, 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 Wellman, IA?

The median last spring frost (32 °F) near 52356 is April 28; after May 11 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Washington station.

When is the first frost in Wellman, IA?

The median first fall frost near 52356 is October 11, giving a median frost-free growing season of 165 days.

When should I plant tomatoes in 52356?

Start tomato seeds indoors around Mar 3 – Mar 17 and set transplants outside around May 5 – May 19, one to three weeks after the median last frost.

How much rain and snow does 52356 get?

About 38.1 inches of precipitation a year (NOAA 1991–2020 normals, North English station).

How hot do summers get in Wellman, IA?

The average high peaks at 85 °F in July, with about 20 days a year at 90 °F or more.

What kind of soil does 52356 have?

The USDA soil survey maps Ladoga at the center of ZIP 52356: silt loam, moderately well drained, pH about 6.6 (neutral).

Did spring come early in Wellman, IA in 2026?

Spring leaf-out near 52356 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 Wellman, IA?

Long-day onions: the longest day near 52356 is 15 h 11 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).