Planting zone for 51540 — Hastings, IA
ZIP code 51540 (Hastings, Mills County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is April 24 and the first fall frost October 13.
Where ZIP 51540 is
Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoomNot 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.
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 ServiceLoading the forecast for Hastings, 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 Hastings, IA
A hard freeze (28 °F) usually ends around April 15 and returns around October 23.
From the NOAA station Red Oak, IA — 14 miles away, elevation 1,040 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 51540
Counted from the median last spring frost (Apr 24) and first fall frost (Oct 13) 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 51540 came on Mar 11 — 18 days earlier than the 1991–2020 average (Mar 29).
Mar 292026
Mar 11
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 Hastings, IA.
Soil in Hastings, IA
The soil mapped at the center of ZIP 51540 is Judson — silty clay loam, well drained.
Map unit: Judson silty clay loam, deep loess, 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 51540; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.
Climate in Hastings, IA
Average high and low, by month
Precipitation by month inches · ❄ = snowfall
NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Red Oak, IA (14 mi away); precipitation: Hastings 4ne, IA (4 mi away). Daylight is calculated from latitude.
Nearby ZIP codes
2 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.
Questions about 51540
What planting zone is ZIP code 51540?
ZIP code 51540 (Hastings, 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 Hastings, IA?
The median last spring frost (32 °F) near 51540 is April 24; after May 8 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Red Oak station.
When is the first frost in Hastings, IA?
The median first fall frost near 51540 is October 13, giving a median frost-free growing season of 169 days.
When should I plant tomatoes in 51540?
Start tomato seeds indoors around Feb 27 – Mar 13 and set transplants outside around May 1 – May 15, one to three weeks after the median last frost.
How much rain and snow does 51540 get?
About 34.9 inches of precipitation a year and 20 inches of snowfall (NOAA 1991–2020 normals, Hastings 4ne station).
How hot do summers get in Hastings, IA?
The average high peaks at 86 °F in July, with about 26 days a year at 90 °F or more.
What kind of soil does 51540 have?
The USDA soil survey maps Judson at the center of ZIP 51540: silty clay loam, well drained, pH about 5.8 (moderately acidic).
Did spring come early in Hastings, IA in 2026?
Spring leaf-out near 51540 came on Mar 11 in 2026, 18 days earlier than the 1991–2020 average (Mar 29), according to the USA National Phenology Network Spring Index.
What kind of onions grow in Hastings, IA?
Long-day onions: the longest day near 51540 is 15 h 08 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).