Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 57640 — Lodgepole, SD

ZIP code 57640 (Lodgepole, Perkins County) is in USDA zone 4b: the coldest winter night averages −25 to −20 °F. The median last spring frost is May 30 and the first fall frost September 11.

Where ZIP 57640 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.

Zone4b−25 to −20 °F

Coldest night−31.7 to −28.9 °C

Last frostMay 30

First frostSep 11

2012 zone4b

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 4b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Lodgepole, SD…

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 Lodgepole, SD

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostMay 30median — 50% chance of a later frost

Safe for tender plantsJune 13only 10% chance of frost after

First fall frostSeptember 11median — 10% chance by Aug 28

Growing season103 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 18 and returns around September 21.

From the NOAA station Lodgepole 5sw, SD — 5 miles away, elevation 2,569 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 57640

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 18 – May 2

SpinachSow outdoors · Apr 18 – May 9

Broccoli, cabbageStart indoors · Mar 21 – Apr 4

Broccoli, cabbageTransplant · May 9 – May 23

Onion setsPlant outdoors · May 2 – May 16

PotatoesPlant outdoors · May 9 – May 23

LettuceSow outdoors · May 2 – May 16

Carrots, beetsSow outdoors · May 9 – May 23

TomatoesStart indoors · Apr 4 – Apr 18

TomatoesTransplant · Jun 6 – Jun 20

Peppers, eggplantStart indoors · Mar 21 – Apr 4

Peppers, eggplantTransplant · Jun 13 – Jun 27

BeansSow outdoors · Jun 6 – Jun 20

Sweet cornSow outdoors · Jun 6 – Jun 20

Cucumbers, squashSow outdoors · Jun 6 – Jun 20

Fall lettuce, spinachSow outdoors · Jul 17 – Jul 31

GarlicPlant cloves · Aug 28 – Oct 2

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 30) and first fall frost (Sep 11) 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 57640 came on Mar 24 — 23 days earlier than the 1991–2020 average (Apr 16).

average
Apr 162026
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).

Soil in Lodgepole, SD

The soil mapped at the center of ZIP 57640 is Vebar — fine sandy loam, well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding

pH6.5neutral; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter2%moderate

Hydrologic groupBwater soaks in moderately

Farmland classNot prime farmlandUSDA classification

Map unit: Vebar-Cohagen fine sandy loams, 6 to 9 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 57640; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Lodgepole, SD

Summer high82 °Faverage high, July

Winter low5 °Faverage low, January

Hot days14days a year at 90 °F or more

Freezing nights214nights a year at 32 °F or less

Growing degree days1,745base 50 °F — the season’s usable heat

Longest day15 h 43 mindaylight on June 21

Shortest day8 h 40 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation16.9 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Lodgepole 5sw, SD (5 mi away); precipitation: Lodgepole 5sw, SD (5 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 4b.

576504b

Ralph, SD · 16 mi

576494b

Prairie City, SD · 21 mi

586394b

Hettinger, ND · 21 mi

South Dakota planting zones →

Questions about 57640

What planting zone is ZIP code 57640?

ZIP code 57640 (Lodgepole, SD) is in USDA hardiness zone 4b on the 2023 map: the coldest night of an average winter reaches −25 to −20 °F (−31.7 to −28.9 °C).

When is the last frost in Lodgepole, SD?

The median last spring frost (32 °F) near 57640 is May 30; after June 13 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Lodgepole 5sw station.

When is the first frost in Lodgepole, SD?

The median first fall frost near 57640 is September 11, giving a median frost-free growing season of 103 days.

When should I plant tomatoes in 57640?

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

How much rain and snow does 57640 get?

About 16.9 inches of precipitation a year (NOAA 1991–2020 normals, Lodgepole 5sw station).

How hot do summers get in Lodgepole, SD?

The average high peaks at 82 °F in July, with about 14 days a year at 90 °F or more.

What kind of soil does 57640 have?

The USDA soil survey maps Vebar at the center of ZIP 57640: fine sandy loam, well drained, pH about 6.5 (neutral).

Did spring come early in Lodgepole, SD in 2026?

Spring leaf-out near 57640 came on Mar 24 in 2026, 23 days earlier than the 1991–2020 average (Apr 16), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Lodgepole, SD?

Long-day onions: the longest day near 57640 is 15 h 43 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).