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

Planting zone for 68440 — Steele City, NE

ZIP code 68440 (Steele City, Jefferson County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 25 and the first fall frost October 15.

Where ZIP 68440 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.

Zone6a−10 to −5 °F
Coldest night−23.3 to −20.6 °C
Last frostApr 25
First frostOct 15
2012 zone5b

Was 5b 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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Steele City, NE…

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 Steele City, NE

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 25median — 50% chance of a later frost
Safe for tender plantsMay 7only 10% chance of frost after
First fall frostOctober 15median — 10% chance by Sep 30
Growing season169 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 14 and returns around October 24.

From the NOAA station Fairbury 5s, NE — 8 miles away, elevation 1,352 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 68440

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 14 – Mar 28
SpinachSow outdoors · Mar 14 – Apr 4
Broccoli, cabbageStart indoors · Feb 14 – Feb 28
Broccoli, cabbageTransplant · Apr 4 – Apr 18
Onion setsPlant outdoors · Mar 28 – Apr 11
PotatoesPlant outdoors · Apr 4 – Apr 18
LettuceSow outdoors · Mar 28 – Apr 11
Carrots, beetsSow outdoors · Apr 4 – Apr 18
TomatoesStart indoors · Feb 28 – Mar 14
TomatoesTransplant · May 2 – May 16
Peppers, eggplantStart indoors · Feb 14 – Feb 28
Peppers, eggplantTransplant · May 9 – May 23
BeansSow outdoors · May 2 – May 16
Sweet cornSow outdoors · May 2 – May 16
Cucumbers, squashSow outdoors · May 2 – May 16
Fall lettuce, spinachSow outdoors · Aug 20 – Sep 3
GarlicPlant cloves · Oct 1 – Nov 5
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 25) and first fall frost (Oct 15) 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 68440 came on Mar 12 — 12 days earlier than the 1991–2020 average (Mar 24).

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 6a in Nebraska

432 plants native to the lower 48 states, recorded in Nebraska, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 31

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Fbitternut hickory75 ft · blooms mid spring · high shade tolerance · to −47 °Fblack locust60 ft · blooms spring · high shade tolerance · to −37 °Fblack oak80 ft · blooms early spring · medium shade tolerance · to −30 °F

Shrubs 57

alderleaf mountain mahogany15 ft · blooms late spring · medium shade tolerance · to −41 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican plum24 ft · blooms mid spring · high shade tolerance · to −38 °Fantelope bitterbrush6 ft · blooms early spring · medium shade tolerance · to −36 °Fbig sagebrush4 ft · blooms mid summer · high shade tolerance · to −43 °F

Wildflowers & perennials 198

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine sweetvetch2 ft · blooms early summer · high shade tolerance · to −62 °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 °FAmerican speedwell0.8 ft · blooms mid summer · low shade tolerance · to −38 °F

Grasses 130

alkali cordgrass3 ft · blooms late summer · high shade tolerance · to −38 °Falkali sacaton3 ft · blooms mid summer · high shade tolerance · to −38 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °Fbasin wildrye5 ft · blooms early spring · high shade tolerance · to −43 °Fbeaked spikerush3 ft · blooms late spring · high shade tolerance · to −28 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °F

Vines 8

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 creeper2 ft · blooms summer · high shade tolerance · to −13 °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 Steele City, NE.

Soil in Steele City, NE

The soil mapped at the center of ZIP 68440 is Lancaster — loam, well drained.

TextureLoama good balance for most vegetables
pH6.0slightly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2%moderate
Hydrologic groupCwater soaks in slowly
Farmland classprime farmlandUSDA classification

Map unit: Lancaster loam, 3 to 7 percent slopes, 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 68440; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Steele City, NE

Summer high88 °Faverage high, July
Winter low14 °Faverage low, January
Hot days42days a year at 90 °F or more
Freezing nights144nights a year at 32 °F or less
Growing degree days3,501base 50 °F — the season’s usable heat
Longest day15 h 01 mindaylight on June 21
Shortest day9 h 19 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation33.2 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 36 °F, low 14 °F 36°14° JanFebruary: average high 41 °F, low 18 °F 41°18° FebMarch: average high 53 °F, low 28 °F 53°28° MarApril: average high 64 °F, low 38 °F 64°38° AprMay: average high 74 °F, low 49 °F 74°49° MayJune: average high 84 °F, low 60 °F 84°60° JunJuly: average high 88 °F, low 65 °F 88°65° JulAugust: average high 86 °F, low 63 °F 86°63° AugSeptember: average high 80 °F, low 53 °F 80°53° SepOctober: average high 67 °F, low 40 °F 67°40° OctNovember: average high 52 °F, low 28 °F 52°28° NovDecember: average high 40 °F, low 18 °F 40°18° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 0.90 in precipitation 0.9 JanFebruary: 1.04 in precipitation 1.0 FebMarch: 1.99 in precipitation 2.0 MarApril: 3.91 in precipitation 3.9 AprMay: 4.80 in precipitation 4.8 MayJune: 4.73 in precipitation 4.7 JunJuly: 3.84 in precipitation 3.8 JulAugust: 3.53 in precipitation 3.5 AugSeptember: 3.46 in precipitation 3.5 SepOctober: 2.30 in precipitation 2.3 OctNovember: 1.47 in precipitation 1.5 NovDecember: 1.25 in precipitation 1.3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Fairbury 5s, NE (8 mi away); precipitation: Steele City 1.8 Nw, NE (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

683506a
Endicott, NE · 5 mi
683426a
Diller, NE · 5 mi
669466a
Hollenberg, KS · 6 mi
684156a
Odell, NE · 10 mi
683776a
Jansen, NE · 11 mi
683526a
Fairbury, NE · 13 mi
669456a
Hanover, KS · 14 mi
669586a
Morrowville, KS · 14 mi

Nebraska planting zones →

Questions about 68440

What planting zone is ZIP code 68440?

ZIP code 68440 (Steele City, NE) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).

When is the last frost in Steele City, NE?

The median last spring frost (32 °F) near 68440 is April 25; after May 7 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Fairbury 5s station.

When is the first frost in Steele City, NE?

The median first fall frost near 68440 is October 15, giving a median frost-free growing season of 169 days.

When should I plant tomatoes in 68440?

Start tomato seeds indoors around Feb 28 – Mar 14 and set transplants outside around May 2 – May 16, one to three weeks after the median last frost.

How much rain and snow does 68440 get?

About 33.2 inches of precipitation a year (NOAA 1991–2020 normals, Steele City 1.8 Nw station).

How hot do summers get in Steele City, NE?

The average high peaks at 88 °F in July, with about 42 days a year at 90 °F or more.

What kind of soil does 68440 have?

The USDA soil survey maps Lancaster at the center of ZIP 68440: loam, well drained, pH about 6.0 (slightly acidic).

Did spring come early in Steele City, NE in 2026?

Spring leaf-out near 68440 came on Mar 12 in 2026, 12 days earlier than the 1991–2020 average (Mar 24), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Steele City, NE?

Long-day onions: the longest day near 68440 is 15 h 01 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 68440 change?

Yes. The 2012 USDA map put 68440 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.