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

Planting zone for 56751 — Roseau, MN

ZIP code 56751 (Roseau, Roseau County) is in USDA zone 3b: the coldest winter night averages −35 to −30 °F. The median last spring frost is May 16 and the first fall frost September 24.

Where ZIP 56751 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.

Zone3b−35 to −30 °F

Coldest night−37.2 to −34.4 °C

Last frostMay 16

First frostSep 24

2012 zone3a

Was 3a 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 3b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Roseau, 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 Roseau, MN

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 16median — 50% chance of a later frost

Safe for tender plantsMay 30only 10% chance of frost after

First fall frostSeptember 24median — 10% chance by Sep 11

Growing season129 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 7 and returns around October 3.

From the NOAA station Warroad, MN — 20 miles away, elevation 1,073 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 56751

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 4 – Apr 18

SpinachSow outdoors · Apr 4 – Apr 25

Broccoli, cabbageStart indoors · Mar 7 – Mar 21

Broccoli, cabbageTransplant · Apr 25 – May 9

Onion setsPlant outdoors · Apr 18 – May 2

PotatoesPlant outdoors · Apr 25 – May 9

LettuceSow outdoors · Apr 18 – May 2

Carrots, beetsSow outdoors · Apr 25 – May 9

TomatoesStart indoors · Mar 21 – Apr 4

TomatoesTransplant · May 23 – Jun 6

Peppers, eggplantStart indoors · Mar 7 – Mar 21

Peppers, eggplantTransplant · May 30 – Jun 13

BeansSow outdoors · May 23 – Jun 6

Sweet cornSow outdoors · May 23 – Jun 6

Cucumbers, squashSow outdoors · May 23 – Jun 6

Fall lettuce, spinachSow outdoors · Jul 30 – Aug 13

GarlicPlant cloves · Sep 10 – Oct 15

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 16) and first fall frost (Sep 24) 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 56751 came on May 7 — 10 days later than the 1991–2020 average (Apr 27).

average
Apr 272026
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 3b in Minnesota

287 plants native to the lower 48 states, recorded in Minnesota, and rated by the USDA to survive −35 °F or colder — the bottom of zone 3b. 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 Roseau, MN.

Soil in Roseau, MN

The soil mapped at the center of ZIP 56751 is Glyndon — very fine sandy loam, somewhat poorly drained.

TextureVery fine sandy loamdrains and warms fast; dries out and needs more feeding

pH7.9alkaline; most vegetables like 6.0–7.0

DrainageSomewhat poorly drainedconsider raised beds

Organic matter3.5%moderate

Hydrologic groupCwater soaks in slowly

Farmland classprime farmlandUSDA classification

Map unit: Glyndon very fine sandy loam, Aspen Parkland, 0 to 2 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 56751; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Roseau, MN

Summer high77 °Faverage high, July

Winter low−8 °Faverage low, January

Hot days2days a year at 90 °F or more

Freezing nights191nights a year at 32 °F or less

Growing degree days1,621base 50 °F — the season’s usable heat

Longest day16 h 10 mindaylight on June 21

Shortest day8 h 15 mindaylight on December 21

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

Precipitation27.7 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: Warroad, MN (20 mi away); precipitation: Warroad, MN (20 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 3b.

Greenbush, MN · 22 mi

567593b

Strathcona, MN · 23 mi

567243b

Gatzke, MN · 25 mi

567373b

Middle River, MN · 30 mi

Minnesota planting zones →

Questions about 56751

What planting zone is ZIP code 56751?

ZIP code 56751 (Roseau, MN) is in USDA hardiness zone 3b on the 2023 map: the coldest night of an average winter reaches −35 to −30 °F (−37.2 to −34.4 °C).

When is the last frost in Roseau, MN?

The median last spring frost (32 °F) near 56751 is May 16; after May 30 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Warroad station.

When is the first frost in Roseau, MN?

The median first fall frost near 56751 is September 24, giving a median frost-free growing season of 129 days.

When should I plant tomatoes in 56751?

Start tomato seeds indoors around Mar 21 – Apr 4 and set transplants outside around May 23 – Jun 6, one to three weeks after the median last frost.

How much rain and snow does 56751 get?

About 27.7 inches of precipitation a year (NOAA 1991–2020 normals, Warroad station).

How hot do summers get in Roseau, MN?

The average high peaks at 77 °F in July, with about 2 days a year at 90 °F or more.

What kind of soil does 56751 have?

The USDA soil survey maps Glyndon at the center of ZIP 56751: very fine sandy loam, somewhat poorly drained, pH about 7.9 (alkaline).

Did spring come early in Roseau, MN in 2026?

Spring leaf-out near 56751 came on May 7 in 2026, 10 days later than the 1991–2020 average (Apr 27), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Roseau, MN?

Long-day onions: the longest day near 56751 is 16 h 10 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 56751 change?

Yes. The 2012 USDA map put 56751 in zone 3a; the 2023 map puts it in zone 3b. The newer map uses 1991–2020 data and more weather stations.