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

Planting zone for 57340 — Fulton, SD

ZIP code 57340 (Fulton, Hanson County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is April 30 and the first fall frost October 5.

Where ZIP 57340 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.

Zone5a−20 to −15 °F

Coldest night−28.9 to −26.1 °C

Last frostApr 30

First frostOct 5

2012 zone4b

Was 4b 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 5a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Fulton, 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 Fulton, SD

JanFebMarAprMayJunJulAugSepOctNovDec

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

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

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

First fall frostOctober 5median — 10% chance by Sep 22

Growing season159 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 20 and returns around October 17.

From the NOAA station Mitchell Municipal Airport, SD — 9 miles away, elevation 1,303 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 57340

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 19 – Apr 2

SpinachSow outdoors · Mar 19 – Apr 9

Broccoli, cabbageStart indoors · Feb 19 – Mar 5

Broccoli, cabbageTransplant · Apr 9 – Apr 23

Onion setsPlant outdoors · Apr 2 – Apr 16

PotatoesPlant outdoors · Apr 9 – Apr 23

LettuceSow outdoors · Apr 2 – Apr 16

Carrots, beetsSow outdoors · Apr 9 – Apr 23

TomatoesStart indoors · Mar 5 – Mar 19

TomatoesTransplant · May 7 – May 21

Peppers, eggplantStart indoors · Feb 19 – Mar 5

Peppers, eggplantTransplant · May 14 – May 28

BeansSow outdoors · May 7 – May 21

Sweet cornSow outdoors · May 7 – May 21

Cucumbers, squashSow outdoors · May 7 – May 21

Fall lettuce, spinachSow outdoors · Aug 10 – Aug 24

GarlicPlant cloves · Sep 21 – Oct 26

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 30) and first fall frost (Oct 5) 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 57340 came on Mar 25 — 17 days earlier than the 1991–2020 average (Apr 11).

average
Apr 112026
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).

Native plants for zone 5a in South Dakota

452 plants native to the lower 48 states, recorded in South Dakota, and rated by the USDA to survive −20 °F or colder — the bottom of zone 5a. Each links to its USDA PLANTS profile.

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 Fulton, SD.

Soil in Fulton, SD

The soil mapped at the center of ZIP 57340 is Bon — loam, moderately well drained.

TextureLoama good balance for most vegetables

pH7.5slightly alkaline; most vegetables like 6.0–7.0

DrainageModerately well drainednatural drainage class

Organic matter5%high

Hydrologic groupCwater soaks in slowly

Farmland classprime farmlandUSDA classification

Map unit: Bon loam, 0 to 2 percent slopes, rarely flooded.

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 57340; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Fulton, SD

Summer high87 °Faverage high, July

Winter low9 °Faverage low, January

Hot days28days a year at 90 °F or more

Freezing nights156nights a year at 32 °F or less

Growing degree days3,034base 50 °F — the season’s usable heat

Longest day15 h 28 mindaylight on June 21

Shortest day8 h 55 mindaylight on December 21

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

Precipitation24.9 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: Mitchell Municipal Airport, SD (9 mi away); precipitation: Fulton 9.4 N, SD (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

573115a

Alexandria, SD · 11 mi

South Dakota planting zones →

Questions about 57340

What planting zone is ZIP code 57340?

ZIP code 57340 (Fulton, SD) is in USDA hardiness zone 5a on the 2023 map: the coldest night of an average winter reaches −20 to −15 °F (−28.9 to −26.1 °C).

When is the last frost in Fulton, SD?

The median last spring frost (32 °F) near 57340 is April 30; after May 13 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Mitchell Municipal Airport station.

When is the first frost in Fulton, SD?

The median first fall frost near 57340 is October 5, giving a median frost-free growing season of 159 days.

When should I plant tomatoes in 57340?

Start tomato seeds indoors around Mar 5 – Mar 19 and set transplants outside around May 7 – May 21, one to three weeks after the median last frost.

How much rain and snow does 57340 get?

About 24.9 inches of precipitation a year (NOAA 1991–2020 normals, Fulton 9.4 N station).

How hot do summers get in Fulton, SD?

The average high peaks at 87 °F in July, with about 28 days a year at 90 °F or more.

What kind of soil does 57340 have?

The USDA soil survey maps Bon at the center of ZIP 57340: loam, moderately well drained, pH about 7.5 (slightly alkaline).

Did spring come early in Fulton, SD in 2026?

Spring leaf-out near 57340 came on Mar 25 in 2026, 17 days earlier than the 1991–2020 average (Apr 11), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Fulton, SD?

Long-day onions: the longest day near 57340 is 15 h 28 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 57340 change?

Yes. The 2012 USDA map put 57340 in zone 4b; the 2023 map puts it in zone 5a. The newer map uses 1991–2020 data and more weather stations.