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

Planting zone for 68652 — Petersburg, NE

ZIP code 68652 (Petersburg, Boone County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is April 29 and the first fall frost October 9.

Where ZIP 68652 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 29
First frostOct 9
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 Petersburg, 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 Petersburg, NE

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 29median — 50% chance of a later frost
Safe for tender plantsMay 11only 10% chance of frost after
First fall frostOctober 9median — 10% chance by Sep 25
Growing season162 daysfrost-free, median

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

From the NOAA station Elgin, NE — 9 miles away, elevation 1,936 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 68652

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 18 – Apr 1
SpinachSow outdoors · Mar 18 – Apr 8
Broccoli, cabbageStart indoors · Feb 18 – Mar 4
Broccoli, cabbageTransplant · Apr 8 – Apr 22
Onion setsPlant outdoors · Apr 1 – Apr 15
PotatoesPlant outdoors · Apr 8 – Apr 22
LettuceSow outdoors · Apr 1 – Apr 15
Carrots, beetsSow outdoors · Apr 8 – Apr 22
TomatoesStart indoors · Mar 4 – Mar 18
TomatoesTransplant · May 6 – May 20
Peppers, eggplantStart indoors · Feb 18 – Mar 4
Peppers, eggplantTransplant · May 13 – May 27
BeansSow outdoors · May 6 – May 20
Sweet cornSow outdoors · May 6 – May 20
Cucumbers, squashSow outdoors · May 6 – May 20
Fall lettuce, spinachSow outdoors · Aug 14 – Aug 28
GarlicPlant cloves · Sep 25 – Oct 30
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 29) and first fall frost (Oct 9) 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 68652 came on Mar 14 — 21 days earlier than the 1991–2020 average (Apr 4).

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 Nebraska

420 plants native to the lower 48 states, recorded in Nebraska, and rated by the USDA to survive −15 °F or colder — the bottom of zone 5b. 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 55

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 190

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 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 °FVirginia creeper1 ft · blooms late spring · medium shade tolerance · to −28 °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 Petersburg, NE.

Soil in Petersburg, NE

The soil mapped at the center of ZIP 68652 is Moody — silty clay loam, well drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up
pH6.6neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3%moderate
Hydrologic groupCwater soaks in slowly
Farmland classprime farmlandUSDA classification

Map unit: Moody silty clay loam, 2 to 6 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 68652; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Petersburg, NE

Summer high84 °Faverage high, July
Winter low12 °Faverage low, January
Hot days17days a year at 90 °F or more
Freezing nights153nights a year at 32 °F or less
Growing degree days2,925base 50 °F — the season’s usable heat
Longest day15 h 14 mindaylight on June 21
Shortest day9 h 08 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation27.4 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 32 °F, low 12 °F 32°12° JanFebruary: average high 36 °F, low 15 °F 36°15° FebMarch: average high 48 °F, low 25 °F 48°25° MarApril: average high 59 °F, low 35 °F 59°35° AprMay: average high 70 °F, low 48 °F 70°48° MayJune: average high 80 °F, low 59 °F 80°59° JunJuly: average high 84 °F, low 63 °F 84°63° JulAugust: average high 82 °F, low 61 °F 82°61° AugSeptember: average high 75 °F, low 51 °F 75°51° SepOctober: average high 63 °F, low 38 °F 63°38° OctNovember: average high 48 °F, low 26 °F 48°26° NovDecember: average high 35 °F, low 16 °F 35°16° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 0.54 in precipitation 0.5 JanFebruary: 0.71 in precipitation 0.7 FebMarch: 1.47 in precipitation 1.5 MarApril: 2.80 in precipitation 2.8 AprMay: 4.17 in precipitation 4.2 MayJune: 4.14 in precipitation 4.1 JunJuly: 3.09 in precipitation 3.1 JulAugust: 3.88 in precipitation 3.9 AugSeptember: 2.32 in precipitation 2.3 SepOctober: 2.41 in precipitation 2.4 OctNovember: 1.07 in precipitation 1.1 NovDecember: 0.81 in precipitation 0.8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Elgin, NE (9 mi away); precipitation: Elgin 0.3 E, NE (9 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

686205b
Albion, NE · 10 mi
686365b
Elgin, NE · 11 mi
687615a
Oakdale, NE · 13 mi
687585b
Newman Grove, NE · 17 mi
686555b
Primrose, NE · 17 mi
687815a
Tilden, NE · 17 mi
686655a
Spalding, NE · 20 mi
686275b
Cedar Rapids, NE · 22 mi

Nebraska planting zones →

Questions about 68652

What planting zone is ZIP code 68652?

ZIP code 68652 (Petersburg, NE) 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 Petersburg, NE?

The median last spring frost (32 °F) near 68652 is April 29; after May 11 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Elgin station.

When is the first frost in Petersburg, NE?

The median first fall frost near 68652 is October 9, giving a median frost-free growing season of 162 days.

When should I plant tomatoes in 68652?

Start tomato seeds indoors around Mar 4 – Mar 18 and set transplants outside around May 6 – May 20, one to three weeks after the median last frost.

How much rain and snow does 68652 get?

About 27.4 inches of precipitation a year (NOAA 1991–2020 normals, Elgin 0.3 E station).

How hot do summers get in Petersburg, NE?

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 68652 have?

The USDA soil survey maps Moody at the center of ZIP 68652: silty clay loam, well drained, pH about 6.6 (neutral).

Did spring come early in Petersburg, NE in 2026?

Spring leaf-out near 68652 came on Mar 14 in 2026, 21 days earlier than the 1991–2020 average (Apr 4), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Petersburg, NE?

Long-day onions: the longest day near 68652 is 15 h 14 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 68652 change?

Yes. The 2012 USDA map put 68652 in zone 5a; the 2023 map puts it in zone 5b. The newer map uses 1991–2020 data and more weather stations.