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

Planting zone for 50105 — Gilbert, IA

ZIP code 50105 (Gilbert, Story County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is April 26 and the first fall frost October 8.

Where ZIP 50105 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 26
First frostOct 8
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 Gilbert, 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 Gilbert, IA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 26median — 50% chance of a later frost
Safe for tender plantsMay 9only 10% chance of frost after
First fall frostOctober 8median — 10% chance by Sep 23
Growing season164 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 14 and returns around October 19.

From the NOAA station Ames Municipal Airport, IA — 9 miles away, elevation 932 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 50105

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 15 – Mar 29
SpinachSow outdoors · Mar 15 – Apr 5
Broccoli, cabbageStart indoors · Feb 15 – Mar 1
Broccoli, cabbageTransplant · Apr 5 – Apr 19
Onion setsPlant outdoors · Mar 29 – Apr 12
PotatoesPlant outdoors · Apr 5 – Apr 19
LettuceSow outdoors · Mar 29 – Apr 12
Carrots, beetsSow outdoors · Apr 5 – Apr 19
TomatoesStart indoors · Mar 1 – Mar 15
TomatoesTransplant · May 3 – May 17
Peppers, eggplantStart indoors · Feb 15 – Mar 1
Peppers, eggplantTransplant · May 10 – May 24
BeansSow outdoors · May 3 – May 17
Sweet cornSow outdoors · May 3 – May 17
Cucumbers, squashSow outdoors · May 3 – May 17
Fall lettuce, spinachSow outdoors · Aug 13 – Aug 27
GarlicPlant cloves · Sep 24 – Oct 29
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 26) and first fall frost (Oct 8) 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 50105 came on Mar 24 — 14 days earlier than the 1991–2020 average (Apr 7).

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 Gilbert, IA.

Soil in Gilbert, IA

The soil mapped at the center of ZIP 50105 is Clarion — loam, moderately well drained.

TextureLoama good balance for most vegetables
pH6.2slightly acidic; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter3.5%moderate
Hydrologic groupCwater soaks in slowly
Farmland classprime farmlandUSDA classification

Map unit: Clarion loam, 2 to 6 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 50105; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Gilbert, IA

Summer high84 °Faverage high, July
Winter low11 °Faverage low, January
Hot days17days a year at 90 °F or more
Freezing nights147nights a year at 32 °F or less
Growing degree days3,021base 50 °F — the season’s usable heat
Longest day15 h 15 mindaylight on June 21
Shortest day9 h 06 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation37.9 inper year, rain and melted snow

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 29 °F, low 11 °F 29°11° JanFebruary: average high 33 °F, low 15 °F 33°15° FebMarch: average high 47 °F, low 27 °F 47°27° MarApril: average high 61 °F, low 38 °F 61°38° AprMay: average high 72 °F, low 50 °F 72°50° MayJune: average high 81 °F, low 60 °F 81°60° JunJuly: average high 84 °F, low 63 °F 84°63° JulAugust: average high 82 °F, low 60 °F 82°60° AugSeptember: average high 76 °F, low 51 °F 76°51° SepOctober: average high 63 °F, low 39 °F 63°39° 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

0″1″2″3″4″5″6″January: 0.97 in precipitation 1.0 JanFebruary: 1.23 in precipitation 1.2 FebMarch: 2.15 in precipitation 2.1 MarApril: 3.87 in precipitation 3.9 AprMay: 5.23 in precipitation 5.2 MayJune: 5.41 in precipitation 5.4 JunJuly: 4.55 in precipitation 4.5 JulAugust: 4.59 in precipitation 4.6 AugSeptember: 3.63 in precipitation 3.6 SepOctober: 2.75 in precipitation 2.8 OctNovember: 1.87 in precipitation 1.9 NovDecember: 1.69 in precipitation 1.7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Ames Municipal Airport, IA (9 mi away); precipitation: Gilbert 0.2 W, IA (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

4 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

502485a
Story City, IA · 5 mi
500145b
Ames, IA · 6 mi
500125b
Ames, IA · 6 mi
500105b
Ames, IA · 7 mi
500135b
Ames, IA · 7 mi
502315a
Randall, IA · 9 mi
502365a
Roland, IA · 9 mi
500365a
Boone, IA · 11 mi

Iowa planting zones →

Questions about 50105

What planting zone is ZIP code 50105?

ZIP code 50105 (Gilbert, 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 Gilbert, IA?

The median last spring frost (32 °F) near 50105 is April 26; after May 9 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Ames Municipal Airport station.

When is the first frost in Gilbert, IA?

The median first fall frost near 50105 is October 8, giving a median frost-free growing season of 164 days.

When should I plant tomatoes in 50105?

Start tomato seeds indoors around Mar 1 – Mar 15 and set transplants outside around May 3 – May 17, one to three weeks after the median last frost.

How much rain and snow does 50105 get?

About 37.9 inches of precipitation a year (NOAA 1991–2020 normals, Gilbert 0.2 W station).

How hot do summers get in Gilbert, IA?

The average high peaks at 84 °F in July, with about 17 days a year at 90 °F or more.

What kind of soil does 50105 have?

The USDA soil survey maps Clarion at the center of ZIP 50105: loam, moderately well drained, pH about 6.2 (slightly acidic).

Did spring come early in Gilbert, IA in 2026?

Spring leaf-out near 50105 came on Mar 24 in 2026, 14 days earlier than the 1991–2020 average (Apr 7), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Gilbert, IA?

Long-day onions: the longest day near 50105 is 15 h 15 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 50105 change?

Yes. The 2012 USDA map put 50105 in zone 5a; the 2023 map puts it in zone 5b. The newer map uses 1991–2020 data and more weather stations.