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

Planting zone for 50311 — Des Moines, IA

ZIP code 50311 (Des Moines, Polk County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is April 18 and the first fall frost October 20.

Where ZIP 50311 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 18
First frostOct 20
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 Des Moines, 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 Des Moines, IA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 18median — 50% chance of a later frost
Safe for tender plantsMay 2only 10% chance of frost after
First fall frostOctober 20median — 10% chance by Oct 4
Growing season184 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 8 and returns around October 30.

From the NOAA station Des Moines Intl Airport, IA — 5 miles away, elevation 958 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 50311

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 7 – Mar 21
SpinachSow outdoors · Mar 7 – Mar 28
Broccoli, cabbageStart indoors · Feb 7 – Feb 21
Broccoli, cabbageTransplant · Mar 28 – Apr 11
Onion setsPlant outdoors · Mar 21 – Apr 4
PotatoesPlant outdoors · Mar 28 – Apr 11
LettuceSow outdoors · Mar 21 – Apr 4
Carrots, beetsSow outdoors · Mar 28 – Apr 11
TomatoesStart indoors · Feb 21 – Mar 7
TomatoesTransplant · Apr 25 – May 9
Peppers, eggplantStart indoors · Feb 7 – Feb 21
Peppers, eggplantTransplant · May 2 – May 16
BeansSow outdoors · Apr 25 – May 9
Sweet cornSow outdoors · Apr 25 – May 9
Cucumbers, squashSow outdoors · Apr 25 – May 9
Fall lettuce, spinachSow outdoors · Aug 25 – Sep 8
GarlicPlant cloves · Oct 6 – Nov 10
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 18) and first fall frost (Oct 20) 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 50311 came on Mar 20 — 14 days earlier than the 1991–2020 average (Apr 3).

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

Shrubs 77

Wildflowers & perennials 191

Grasses 136

Vines 7

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 Des Moines, IA.

Soil in Des Moines, IA

The soil mapped at the center of ZIP 50311 is Clarion — loam, well drained.

TextureLoama good balance for most vegetables
pH6.5neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3.5%moderate
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Clarion-Urban land complex, 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 50311; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Des Moines, IA

Summer high86 °Faverage high, July
Winter low14 °Faverage low, January
Hot days22days a year at 90 °F or more
Freezing nights128nights a year at 32 °F or less
Growing degree days3,476base 50 °F — the season’s usable heat
Longest day15 h 12 mindaylight on June 21
Shortest day9 h 09 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation38.7 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 31 °F, low 14 °F 31°14° JanFebruary: average high 36 °F, low 18 °F 36°18° FebMarch: average high 49 °F, low 30 °F 49°30° MarApril: average high 62 °F, low 41 °F 62°41° AprMay: average high 72 °F, low 52 °F 72°52° MayJune: average high 82 °F, low 62 °F 82°62° JunJuly: average high 86 °F, low 66 °F 86°66° JulAugust: average high 84 °F, low 64 °F 84°64° AugSeptember: average high 77 °F, low 55 °F 77°55° SepOctober: average high 63 °F, low 43 °F 63°43° OctNovember: average high 48 °F, low 30 °F 48°30° NovDecember: average high 36 °F, low 20 °F 36°20° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 1.11 in precipitation 1.1 JanFebruary: 1.25 in precipitation 1.3 FebMarch: 2.05 in precipitation 2.0 MarApril: 4.29 in precipitation 4.3 AprMay: 5.32 in precipitation 5.3 MayJune: 5.62 in precipitation 5.6 JunJuly: 4.39 in precipitation 4.4 JulAugust: 4.56 in precipitation 4.6 AugSeptember: 3.53 in precipitation 3.5 SepOctober: 3.00 in precipitation 3.0 OctNovember: 1.96 in precipitation 2.0 NovDecember: 1.59 in precipitation 1.6 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Des Moines Intl Airport, IA (5 mi away); precipitation: Des Moines 4.5 Wnw, IA (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 5b.

All 57 ZIP codes in Des Moines → · Iowa planting zones →

Questions about 50311

What planting zone is ZIP code 50311?

ZIP code 50311 (Des Moines, 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 Des Moines, IA?

The median last spring frost (32 °F) near 50311 is April 18; after May 2 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Des Moines Intl Airport station.

When is the first frost in Des Moines, IA?

The median first fall frost near 50311 is October 20, giving a median frost-free growing season of 184 days.

When should I plant tomatoes in 50311?

Start tomato seeds indoors around Feb 21 – Mar 7 and set transplants outside around Apr 25 – May 9, one to three weeks after the median last frost.

How much rain and snow does 50311 get?

About 38.7 inches of precipitation a year (NOAA 1991–2020 normals, Des Moines 4.5 Wnw station).

How hot do summers get in Des Moines, IA?

The average high peaks at 86 °F in July, with about 22 days a year at 90 °F or more.

What kind of soil does 50311 have?

The USDA soil survey maps Clarion at the center of ZIP 50311: loam, well drained, pH about 6.5 (neutral).

Did spring come early in Des Moines, IA in 2026?

Spring leaf-out near 50311 came on Mar 20 in 2026, 14 days earlier than the 1991–2020 average (Apr 3), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Des Moines, IA?

Long-day onions: the longest day near 50311 is 15 h 12 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).