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

Planting zone for 56538 — Fergus Falls, MN

ZIP code 56538 (Fergus Falls, Otter Tail County) is in USDA zone 4a: the coldest winter night averages −30 to −25 °F. The median last spring frost is May 4 and the first fall frost October 5.

Where ZIP 56538 is

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 4
First frostOct 5
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 Fergus Falls, 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 Fergus Falls, MN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 4median — 50% chance of a later frost
Safe for tender plantsMay 18only 10% chance of frost after
First fall frostOctober 5median — 10% chance by Sep 22
Growing season152 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 26 and returns around October 15.

From the NOAA station Fergus Falls, MN — 2 miles away, elevation 1,250 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 56538

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 23 – Apr 6
SpinachSow outdoors · Mar 23 – Apr 13
Broccoli, cabbageStart indoors · Feb 23 – Mar 9
Broccoli, cabbageTransplant · Apr 13 – Apr 27
Onion setsPlant outdoors · Apr 6 – Apr 20
PotatoesPlant outdoors · Apr 13 – Apr 27
LettuceSow outdoors · Apr 6 – Apr 20
Carrots, beetsSow outdoors · Apr 13 – Apr 27
TomatoesStart indoors · Mar 9 – Mar 23
TomatoesTransplant · May 11 – May 25
Peppers, eggplantStart indoors · Feb 23 – Mar 9
Peppers, eggplantTransplant · May 18 – Jun 1
BeansSow outdoors · May 11 – May 25
Sweet cornSow outdoors · May 11 – May 25
Cucumbers, squashSow outdoors · May 11 – May 25
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 (May 4) 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 56538 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).

Native plants for zone 4a in Minnesota

445 plants native to the lower 48 states, recorded in Minnesota, and rated by the USDA to survive −30 °F or colder — the bottom of zone 4a. Each links to its USDA PLANTS profile.

Trees 45

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °Farborvitae50 ft · blooms mid spring · medium shade tolerance · to −33 °Fbalsam fir60 ft · blooms mid summer · low shade tolerance · to −43 °Fbalsam poplar80 ft · blooms late spring · high shade tolerance · to −79 °F

Shrubs 77

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican hornbeam30 ft · blooms mid spring · low shade tolerance · to −34 °F

Wildflowers & perennials 173

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °F

Grasses 140

alkali cordgrass3 ft · blooms late summer · high shade tolerance · to −38 °Farctic brome3 ft · blooms early summer · low shade tolerance · to −33 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °Fbasin wildrye5 ft · blooms early spring · high shade tolerance · to −43 °Fbeaked sedge4 ft · blooms late spring · low shade tolerance · to −38 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °F

Vines 3

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °F

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 Fergus Falls, MN.

Soil in Fergus Falls, MN

The soil mapped at the center of ZIP 56538 is Udorthents — loam, well drained.

TextureLoama good balance for most vegetables
pH7.3neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter0.25%low — add compost
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Udorthents, loamy (cut and fill land).

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 56538; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Fergus Falls, MN

Summer high81 °Faverage high, July
Winter low0 °Faverage low, January
Hot days8days a year at 90 °F or more
Freezing nights174nights a year at 32 °F or less
Growing degree days2,356base 50 °F — the season’s usable heat
Longest day15 h 48 mindaylight on June 21
Shortest day8 h 36 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation26.9 inper year, rain and melted snow

Average high and low, by month

−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 18 °F, low 0 °F 18°0° JanFebruary: average high 22 °F, low 3 °F 22°3° FebMarch: average high 36 °F, low 18 °F 36°18° MarApril: average high 53 °F, low 32 °F 53°32° AprMay: average high 67 °F, low 45 °F 67°45° MayJune: average high 76 °F, low 56 °F 76°56° JunJuly: average high 81 °F, low 61 °F 81°61° JulAugust: average high 79 °F, low 57 °F 79°57° AugSeptember: average high 71 °F, low 49 °F 71°49° SepOctober: average high 56 °F, low 35 °F 56°35° OctNovember: average high 38 °F, low 21 °F 38°21° NovDecember: average high 24 °F, low 8 °F 24°8° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 1.29 in precipitation 1.3 JanFebruary: 0.83 in precipitation 0.8 FebMarch: 1.15 in precipitation 1.1 MarApril: 2.00 in precipitation 2.0 AprMay: 3.86 in precipitation 3.9 MayJune: 4.35 in precipitation 4.3 JunJuly: 3.28 in precipitation 3.3 JulAugust: 2.95 in precipitation 3.0 AugSeptember: 3.04 in precipitation 3.0 SepOctober: 2.37 in precipitation 2.4 OctNovember: 1.04 in precipitation 1.0 NovDecember: 0.71 in precipitation 0.7 Dec

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

Nearby ZIP codes

All 8 nearest ZIP codes share zone 4a.

565374a
Fergus Falls, MN · <1 mi
565334a
Elizabeth, MN · 9 mi
563244a
Dalton, MN · 11 mi
565864a
Underwood, MN · 12 mi
565434a
Foxhome, MN · 12 mi
565344a
Erhard, MN · 13 mi
565794a
Rothsay, MN · 18 mi
565904a
Wendell, MN · 18 mi

All 2 ZIP codes in Fergus Falls → · Minnesota planting zones →

Questions about 56538

What planting zone is ZIP code 56538?

ZIP code 56538 (Fergus Falls, 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 Fergus Falls, MN?

The median last spring frost (32 °F) near 56538 is May 4; after May 18 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Fergus Falls station.

When is the first frost in Fergus Falls, MN?

The median first fall frost near 56538 is October 5, giving a median frost-free growing season of 152 days.

When should I plant tomatoes in 56538?

Start tomato seeds indoors around Mar 9 – Mar 23 and set transplants outside around May 11 – May 25, one to three weeks after the median last frost.

How much rain and snow does 56538 get?

About 26.9 inches of precipitation a year (NOAA 1991–2020 normals, Fergus Falls station).

How hot do summers get in Fergus Falls, MN?

The average high peaks at 81 °F in July, with about 8 days a year at 90 °F or more.

What kind of soil does 56538 have?

The USDA soil survey maps Udorthents at the center of ZIP 56538: loam, well drained, pH about 7.3 (neutral).

Did spring come early in Fergus Falls, MN in 2026?

Spring leaf-out near 56538 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 Fergus Falls, MN?

Long-day onions: the longest day near 56538 is 15 h 48 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).