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

Planting zone for 68433 — Salem, NE

ZIP code 68433 (Salem, Richardson County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 18 and the first fall frost October 17.

Where ZIP 68433 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 18
First frostOct 17
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 Salem, 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 Salem, NE

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 17median — 10% chance by Oct 1
Growing season180 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 8 and returns around October 26.

From the NOAA station Falls City Brenner Field, NE — 8 miles away, elevation 981 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 68433

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 22 – Sep 5
GarlicPlant cloves · Oct 3 – Nov 7
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 18) and first fall frost (Oct 17) 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 68433 came on Mar 11 — 14 days earlier than the 1991–2020 average (Mar 25).

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).

Soil in Salem, NE

The soil mapped at the center of ZIP 68433 is Aksarben — silty clay loam, well drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up
pH5.7moderately acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3.5%moderate
Hydrologic groupCwater soaks in slowly
Farmland classprime farmlandUSDA classification

Map unit: Aksarben silty clay loam, 0 to 2 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 68433; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Salem, NE

Summer high88 °Faverage high, July
Winter low17 °Faverage low, January
Hot days41days a year at 90 °F or more
Freezing nights131nights a year at 32 °F or less
Growing degree days3,775base 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)
Precipitation34.5 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 36 °F, low 17 °F 36°17° JanFebruary: average high 42 °F, low 21 °F 42°21° FebMarch: average high 54 °F, low 31 °F 54°31° MarApril: average high 65 °F, low 41 °F 65°41° AprMay: average high 75 °F, low 53 °F 75°53° MayJune: average high 85 °F, low 63 °F 85°63° JunJuly: average high 88 °F, low 66 °F 88°66° JulAugust: average high 87 °F, low 64 °F 87°64° AugSeptember: average high 80 °F, low 55 °F 80°55° SepOctober: average high 67 °F, low 43 °F 67°43° OctNovember: average high 52 °F, low 30 °F 52°30° NovDecember: average high 40 °F, low 21 °F 40°21° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 0.84 in precipitation 0.8 JanFebruary: 1.13 in precipitation 1.1 FebMarch: 2.24 in precipitation 2.2 MarApril: 3.17 in precipitation 3.2 AprMay: 4.82 in precipitation 4.8 MayJune: 4.97 in precipitation 5.0 JunJuly: 4.55 in precipitation 4.5 JulAugust: 3.54 in precipitation 3.5 AugSeptember: 3.44 in precipitation 3.4 SepOctober: 2.70 in precipitation 2.7 OctNovember: 1.86 in precipitation 1.9 NovDecember: 1.22 in precipitation 1.2 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Falls City Brenner Field, NE (8 mi away); precipitation: Verdon 9.5 Ssw, NE (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

683376a
Dawson, NE · 6 mi
684576a
Verdon, NE · 7 mi
665156a
Morrill, KS · 8 mi
683556a
Falls City, NE · 10 mi
684426a
Stella, NE · 13 mi
665346a
Sabetha, KS · 13 mi
683766a
Humboldt, NE · 13 mi
664086a
Bern, KS · 14 mi

Nebraska planting zones →

Questions about 68433

What planting zone is ZIP code 68433?

ZIP code 68433 (Salem, 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 Salem, NE?

The median last spring frost (32 °F) near 68433 is April 18; after May 2 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Falls City Brenner Field station.

When is the first frost in Salem, NE?

The median first fall frost near 68433 is October 17, giving a median frost-free growing season of 180 days.

When should I plant tomatoes in 68433?

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 68433 get?

About 34.5 inches of precipitation a year (NOAA 1991–2020 normals, Verdon 9.5 Ssw station).

How hot do summers get in Salem, NE?

The average high peaks at 88 °F in July, with about 41 days a year at 90 °F or more.

What kind of soil does 68433 have?

The USDA soil survey maps Aksarben at the center of ZIP 68433: silty clay loam, well drained, pH about 5.7 (moderately acidic).

Did spring come early in Salem, NE in 2026?

Spring leaf-out near 68433 came on Mar 11 in 2026, 14 days earlier than the 1991–2020 average (Mar 25), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Salem, NE?

Long-day onions: the longest day near 68433 is 15 h 01 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 68433 change?

Yes. The 2012 USDA map put 68433 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.