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

Planting zone for 56113 — Arco, MN

ZIP code 56113 (Arco, Lincoln County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is May 5 and the first fall frost October 3.

Where ZIP 56113 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 frostMay 5

First frostOct 3

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 Arco, MN…

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 Arco, MN

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 5median — 50% chance of a later frost

Safe for tender plantsMay 18only 10% chance of frost after

First fall frostOctober 3median — 10% chance by Sep 21

Growing season150 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 27 and returns around October 13.

From the NOAA station Marshall, MN — 19 miles away, elevation 1,148 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 56113

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 24 – Apr 7

SpinachSow outdoors · Mar 24 – Apr 14

Broccoli, cabbageStart indoors · Feb 24 – Mar 10

Broccoli, cabbageTransplant · Apr 14 – Apr 28

Onion setsPlant outdoors · Apr 7 – Apr 21

PotatoesPlant outdoors · Apr 14 – Apr 28

LettuceSow outdoors · Apr 7 – Apr 21

Carrots, beetsSow outdoors · Apr 14 – Apr 28

TomatoesStart indoors · Mar 10 – Mar 24

TomatoesTransplant · May 12 – May 26

Peppers, eggplantStart indoors · Feb 24 – Mar 10

Peppers, eggplantTransplant · May 19 – Jun 2

BeansSow outdoors · May 12 – May 26

Sweet cornSow outdoors · May 12 – May 26

Cucumbers, squashSow outdoors · May 12 – May 26

Fall lettuce, spinachSow outdoors · Aug 8 – Aug 22

GarlicPlant cloves · Sep 19 – Oct 24

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 5) and first fall frost (Oct 3) 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 56113 came on Apr 8 — 10 days earlier than the 1991–2020 average (Apr 18).

average
Apr 182026
Apr 8

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 Arco, MN

The soil mapped at the center of ZIP 56113 is Sverdrup — sandy loam, well drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding

pH7.0neutral; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter2.5%moderate

Hydrologic groupAwater soaks in fast

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Sverdrup sandy loam, 2 to 6 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 56113; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Arco, MN

Summer high85 °Faverage high, July

Winter low4 °Faverage low, January

Hot days18days a year at 90 °F or more

Freezing nights158nights a year at 32 °F or less

Growing degree days2,760base 50 °F — the season’s usable heat

Longest day15 h 32 mindaylight on June 21

Shortest day8 h 50 mindaylight on December 21

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

Precipitation29.9 inper year, rain and melted snow

Snowfall42 inper year

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Marshall, MN (19 mi away); precipitation: Tyler, MN (9 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

Lake Benton, MN · 10 mi

562395a

Ghent, MN · 14 mi

561364b

Hendricks, MN · 14 mi

562645a

Minneota, MN · 15 mi

Minnesota planting zones →

Questions about 56113

What planting zone is ZIP code 56113?

ZIP code 56113 (Arco, MN) 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 Arco, MN?

The median last spring frost (32 °F) near 56113 is May 5; after May 18 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Marshall station.

When is the first frost in Arco, MN?

The median first fall frost near 56113 is October 3, giving a median frost-free growing season of 150 days.

When should I plant tomatoes in 56113?

Start tomato seeds indoors around Mar 10 – Mar 24 and set transplants outside around May 12 – May 26, one to three weeks after the median last frost.

How much rain and snow does 56113 get?

About 29.9 inches of precipitation a year and 42 inches of snowfall (NOAA 1991–2020 normals, Tyler station).

How hot do summers get in Arco, MN?

The average high peaks at 85 °F in July, with about 18 days a year at 90 °F or more.

What kind of soil does 56113 have?

The USDA soil survey maps Sverdrup at the center of ZIP 56113: sandy loam, well drained, pH about 7.0 (neutral).

Did spring come early in Arco, MN in 2026?

Spring leaf-out near 56113 came on Apr 8 in 2026, 10 days earlier than the 1991–2020 average (Apr 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Arco, MN?

Long-day onions: the longest day near 56113 is 15 h 32 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 56113 change?

Yes. The 2012 USDA map put 56113 in zone 4b; the 2023 map puts it in zone 5a. The newer map uses 1991–2020 data and more weather stations.