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

Planting zone for 50057 — Columbia, IA

ZIP code 50057 (Columbia, Marion County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is April 20 and the first fall frost October 19.

Where ZIP 50057 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 20
First frostOct 19
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 Columbia, 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 Columbia, IA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 20median — 50% chance of a later frost
Safe for tender plantsMay 4only 10% chance of frost after
First fall frostOctober 19median — 10% chance by Oct 1
Growing season180 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 10 and returns around October 29.

From the NOAA station Knoxville, IA — 10 miles away, elevation 896 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 50057

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 9 – Mar 23
SpinachSow outdoors · Mar 9 – Mar 30
Broccoli, cabbageStart indoors · Feb 9 – Feb 23
Broccoli, cabbageTransplant · Mar 30 – Apr 13
Onion setsPlant outdoors · Mar 23 – Apr 6
PotatoesPlant outdoors · Mar 30 – Apr 13
LettuceSow outdoors · Mar 23 – Apr 6
Carrots, beetsSow outdoors · Mar 30 – Apr 13
TomatoesStart indoors · Feb 23 – Mar 9
TomatoesTransplant · Apr 27 – May 11
Peppers, eggplantStart indoors · Feb 9 – Feb 23
Peppers, eggplantTransplant · May 4 – May 18
BeansSow outdoors · Apr 27 – May 11
Sweet cornSow outdoors · Apr 27 – May 11
Cucumbers, squashSow outdoors · Apr 27 – May 11
Fall lettuce, spinachSow outdoors · Aug 24 – Sep 7
GarlicPlant cloves · Oct 5 – Nov 9
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 20) and first fall frost (Oct 19) 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 50057 came on Mar 15 — 17 days earlier than the 1991–2020 average (Apr 1).

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.

Trees 49

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican chestnut115 ft · blooms early summer · high shade tolerance · to −33 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Farborvitae50 ft · blooms mid spring · medium shade tolerance · to −33 °Fbalsam fir60 ft · blooms mid summer · low shade tolerance · to −43 °F

Shrubs 77

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican hornbeam30 ft · blooms mid spring · low shade tolerance · to −34 °F

Wildflowers & perennials 191

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °F

Grasses 136

arctic brome3 ft · blooms early summer · low shade tolerance · to −33 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °FBicknell's sedge3 ft · blooms late spring · low shade tolerance · to −38 °Fbig bluestem6 ft · blooms summer · high shade tolerance · to −46 °Fblue grama1 ft · blooms early summer · high shade tolerance · to −43 °F

Vines 7

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Ffrost grape83 ft · blooms late spring · medium shade tolerance · to −23 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °Ftrumpet honeysuckle16 ft · blooms late summer · low shade tolerance · to −33 °F

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 Columbia, IA.

Soil in Columbia, IA

The soil mapped at the center of ZIP 50057 is Pershing — silt loam, somewhat poorly drained.

TextureSilt loama good balance for most vegetables
pH5.9moderately acidic; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter2.5%moderate
Hydrologic groupDwater soaks in very slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Pershing silt loam, 5 to 9 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 50057; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Columbia, IA

Summer high85 °Faverage high, July
Winter low13 °Faverage low, January
Hot days20days a year at 90 °F or more
Freezing nights133nights a year at 32 °F or less
Growing degree days3,279base 50 °F — the season’s usable heat
Longest day15 h 09 mindaylight on June 21
Shortest day9 h 12 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation37.5 inper year, rain and melted snow

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 30 °F, low 13 °F 30°13° JanFebruary: average high 35 °F, low 17 °F 35°17° FebMarch: average high 48 °F, low 28 °F 48°28° MarApril: average high 61 °F, low 39 °F 61°39° AprMay: average high 71 °F, low 51 °F 71°51° MayJune: average high 81 °F, low 61 °F 81°61° JunJuly: average high 85 °F, low 66 °F 85°66° JulAugust: average high 83 °F, low 63 °F 83°63° AugSeptember: average high 76 °F, low 54 °F 76°54° SepOctober: average high 63 °F, low 42 °F 63°42° OctNovember: average high 48 °F, low 30 °F 48°30° NovDecember: average high 36 °F, low 19 °F 36°19° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 1.15 in precipitation 1.1 JanFebruary: 1.67 in precipitation 1.7 FebMarch: 1.87 in precipitation 1.9 MarApril: 3.85 in precipitation 3.9 AprMay: 4.98 in precipitation 5.0 MayJune: 5.61 in precipitation 5.6 JunJuly: 4.34 in precipitation 4.3 JulAugust: 3.89 in precipitation 3.9 AugSeptember: 3.66 in precipitation 3.7 SepOctober: 3.06 in precipitation 3.1 OctNovember: 1.80 in precipitation 1.8 NovDecember: 1.57 in precipitation 1.6 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Knoxville, IA (10 mi away); precipitation: Knoxville, IA (10 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 5b.

501635b
Melcher Dallas, IA · 6 mi
500625b
Melcher Dallas, IA · 7 mi
501165b
Hamilton, IA · 8 mi
501385b
Knoxville, IA · 9 mi
502725b
Williamson, IA · 9 mi
501505b
Lovilia, IA · 9 mi
501395b
Lacona, IA · 12 mi
500445b
Bussey, IA · 12 mi

Iowa planting zones →

Questions about 50057

What planting zone is ZIP code 50057?

ZIP code 50057 (Columbia, 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 Columbia, IA?

The median last spring frost (32 °F) near 50057 is April 20; after May 4 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Knoxville station.

When is the first frost in Columbia, IA?

The median first fall frost near 50057 is October 19, giving a median frost-free growing season of 180 days.

When should I plant tomatoes in 50057?

Start tomato seeds indoors around Feb 23 – Mar 9 and set transplants outside around Apr 27 – May 11, one to three weeks after the median last frost.

How much rain and snow does 50057 get?

About 37.5 inches of precipitation a year (NOAA 1991–2020 normals, Knoxville station).

How hot do summers get in Columbia, 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 50057 have?

The USDA soil survey maps Pershing at the center of ZIP 50057: silt loam, somewhat poorly drained, pH about 5.9 (moderately acidic).

Did spring come early in Columbia, IA in 2026?

Spring leaf-out near 50057 came on Mar 15 in 2026, 17 days earlier than the 1991–2020 average (Apr 1), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Columbia, IA?

Long-day onions: the longest day near 50057 is 15 h 09 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).