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

Planting zone for 56579 — Rothsay, MN

ZIP code 56579 (Rothsay, Wilkin County) is in USDA zone 4a: the coldest winter night averages −30 to −25 °F. The median last spring frost is May 5 and the first fall frost October 3.

Where ZIP 56579 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.

Zone4a−30 to −25 °F
Coldest night−34.4 to −31.7 °C
Last frostMay 5
First frostOct 3
2012 zone4a

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 4a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Rothsay, 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 Rothsay, 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 20only 10% chance of frost after
First fall frostOctober 3median — 10% chance by Sep 21
Growing season149 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 28 and returns around October 12.

From the NOAA station Rothsay, MN — 2 miles away, elevation 1,204 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 56579

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 56579 came on Apr 21 — about the same time as the 1991–2020 average (Apr 21).

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 Rothsay, MN

The soil mapped at the center of ZIP 56579 is Urness — mucky silt loam, very poorly drained.

TextureMucky silt loama good balance for most vegetables
pH7.9alkaline; most vegetables like 6.0–7.0
DrainageVery poorly drainedconsider raised beds
Organic matter15%high
Hydrologic groupB/Dmoderate when drained; wet otherwise
Farmland classPrime farmland if drainedUSDA classification

Map unit: Urness mucky silt loam, 0 to 1 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 56579; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Rothsay, MN

Summer high80 °Faverage high, July
Winter low−1 °Faverage low, January
Hot days5days a year at 90 °F or more
Freezing nights171nights a year at 32 °F or less
Growing degree days2,308base 50 °F — the season’s usable heat
Longest day15 h 49 mindaylight on June 21
Shortest day8 h 35 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation24.8 inper year, rain and melted snow
Snowfall50 inper year

Average high and low, by month

−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 18 °F, low -1 °F 18°−1° JanFebruary: average high 23 °F, low 3 °F 23°3° FebMarch: average high 36 °F, low 17 °F 36°17° MarApril: average high 53 °F, low 31 °F 53°31° AprMay: average high 67 °F, low 45 °F 67°45° MayJune: average high 76 °F, low 56 °F 76°56° JunJuly: average high 80 °F, low 60 °F 80°60° JulAugust: average high 78 °F, low 58 °F 78°58° AugSeptember: average high 70 °F, low 49 °F 70°49° SepOctober: average high 55 °F, low 35 °F 55°35° OctNovember: average high 38 °F, low 21 °F 38°21° NovDecember: average high 24 °F, low 7 °F 24°7° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″January: 0.75 in precipitation, 11.4 in snowfall 0.8❄11 JanFebruary: 0.63 in precipitation, 7.7 in snowfall 0.6❄8 FebMarch: 1.08 in precipitation, 7.2 in snowfall 1.1❄7 MarApril: 2.06 in precipitation, 4.1 in snowfall 2.1❄4 AprMay: 3.27 in precipitation 3.3 MayJune: 3.93 in precipitation 3.9 JunJuly: 3.43 in precipitation 3.4 JulAugust: 2.72 in precipitation 2.7 AugSeptember: 2.75 in precipitation 2.8 SepOctober: 2.34 in precipitation, 1.6 in snowfall 2.3❄2 OctNovember: 0.92 in precipitation, 6.9 in snowfall 0.9❄7 NovDecember: 0.89 in precipitation, 10.7 in snowfall 0.9❄11 Dec

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

Nearby ZIP codes

All 8 nearest ZIP codes share zone 4a.

565334a
Elizabeth, MN · 10 mi
565434a
Foxhome, MN · 12 mi
565534a
Kent, MN · 13 mi
565144a
Barnesville, MN · 13 mi
565204a
Breckenridge, MN · 14 mi
565724a
Pelican Rapids, MN · 16 mi
565344a
Erhard, MN · 16 mi
565944a
Wolverton, MN · 16 mi

Minnesota planting zones →

Questions about 56579

What planting zone is ZIP code 56579?

ZIP code 56579 (Rothsay, MN) is in USDA hardiness zone 4a on the 2023 map: the coldest night of an average winter reaches −30 to −25 °F (−34.4 to −31.7 °C).

When is the last frost in Rothsay, MN?

The median last spring frost (32 °F) near 56579 is May 5; after May 20 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Rothsay station.

When is the first frost in Rothsay, MN?

The median first fall frost near 56579 is October 3, giving a median frost-free growing season of 149 days.

When should I plant tomatoes in 56579?

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 56579 get?

About 24.8 inches of precipitation a year and 50 inches of snowfall (NOAA 1991–2020 normals, Rothsay station).

How hot do summers get in Rothsay, MN?

The average high peaks at 80 °F in July, with about 5 days a year at 90 °F or more.

What kind of soil does 56579 have?

The USDA soil survey maps Urness at the center of ZIP 56579: mucky silt loam, very poorly drained, pH about 7.9 (alkaline).

Did spring come early in Rothsay, MN in 2026?

Spring leaf-out near 56579 came on Apr 21 in 2026, about the same as the 1991–2020 average (Apr 21), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Rothsay, MN?

Long-day onions: the longest day near 56579 is 15 h 49 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).