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

Planting zone for 55782 — Soudan, MN

ZIP code 55782 (Soudan, St. Louis County) is in USDA zone 3a: the coldest winter night averages −40 to −35 °F. The median last spring frost is May 28 and the first fall frost September 14.

Where ZIP 55782 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.

Zone3a−40 to −35 °F

Coldest night−40 to −37.2 °C

Last frostMay 28

First frostSep 14

2012 zone3a

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 3a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Soudan, 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 Soudan, MN

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 28median — 50% chance of a later frost

Safe for tender plantsJune 16only 10% chance of frost after

First fall frostSeptember 14median — 10% chance by Aug 29

Growing season108 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 13 and returns around September 26.

From the NOAA station Babbitt, MN — 14 miles away, elevation 1,480 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 55782

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 16 – Apr 30

SpinachSow outdoors · Apr 16 – May 7

Broccoli, cabbageStart indoors · Mar 19 – Apr 2

Broccoli, cabbageTransplant · May 7 – May 21

Onion setsPlant outdoors · Apr 30 – May 14

PotatoesPlant outdoors · May 7 – May 21

LettuceSow outdoors · Apr 30 – May 14

Carrots, beetsSow outdoors · May 7 – May 21

TomatoesStart indoors · Apr 2 – Apr 16

TomatoesTransplant · Jun 4 – Jun 18

Peppers, eggplantStart indoors · Mar 19 – Apr 2

Peppers, eggplantTransplant · Jun 11 – Jun 25

BeansSow outdoors · Jun 4 – Jun 18

Sweet cornSow outdoors · Jun 4 – Jun 18

Cucumbers, squashSow outdoors · Jun 4 – Jun 18

Fall lettuce, spinachSow outdoors · Jul 20 – Aug 3

GarlicPlant cloves · Aug 31 – Oct 5

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 28) and first fall frost (Sep 14) 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 55782 came on May 7 — 7 days later than the 1991–2020 average (Apr 30).

average
Apr 302026
May 7

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 3a in Minnesota

113 plants native to the lower 48 states, recorded in Minnesota, and rated by the USDA to survive −40 °F or colder — the bottom of zone 3a. 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 Soudan, MN.

Soil in Soudan, MN

The soil mapped at the center of ZIP 55782 is Bowstring — muck, very poorly drained.

TextureMucktop layer

DrainageVery poorly drainedconsider raised beds

Organic matter65%high

Hydrologic groupA/Ddrains fast once dried out; wet otherwise

Farmland classNot prime farmlandUSDA classification

Map unit: Bowstring and Fluvaquents, loamy, 0 to 2 percent slopes, frequently 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 55782; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Soudan, MN

Summer high77 °Faverage high, July

Winter low−7 °Faverage low, January

Hot days4days a year at 90 °F or more

Freezing nights220nights a year at 32 °F or less

Growing degree days1,452base 50 °F — the season’s usable heat

Longest day16 h 01 mindaylight on June 21

Shortest day8 h 23 mindaylight on December 21

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

Precipitation28.2 inper year, rain and melted snow

Snowfall69 inper year

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Tower 2s, MN (5 mi away); precipitation: Tower 2s, MN (5 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

557903a

Tower, MN · 8 mi

557323a

Embarrass, MN · 10 mi

Hoyt Lakes, MN · 24 mi

557313b

Ely, MN · 24 mi

Minnesota planting zones →

Questions about 55782

What planting zone is ZIP code 55782?

ZIP code 55782 (Soudan, MN) is in USDA hardiness zone 3a on the 2023 map: the coldest night of an average winter reaches −40 to −35 °F (−40 to −37.2 °C).

When is the last frost in Soudan, MN?

The median last spring frost (32 °F) near 55782 is May 28; after June 16 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Babbitt station.

When is the first frost in Soudan, MN?

The median first fall frost near 55782 is September 14, giving a median frost-free growing season of 108 days.

When should I plant tomatoes in 55782?

Start tomato seeds indoors around Apr 2 – Apr 16 and set transplants outside around Jun 4 – Jun 18, one to three weeks after the median last frost.

How much rain and snow does 55782 get?

About 28.2 inches of precipitation a year and 69 inches of snowfall (NOAA 1991–2020 normals, Tower 2s station).

How hot do summers get in Soudan, MN?

The average high peaks at 77 °F in July, with about 4 days a year at 90 °F or more.

What kind of soil does 55782 have?

The USDA soil survey maps Bowstring at the center of ZIP 55782: muck, very poorly drained.

Did spring come early in Soudan, MN in 2026?

Spring leaf-out near 55782 came on May 7 in 2026, 7 days later than the 1991–2020 average (Apr 30), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Soudan, MN?

Long-day onions: the longest day near 55782 is 16 h 01 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).