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

Planting zone for 56541 — Flom, MN

ZIP code 56541 (Flom, Norman County) is in USDA zone 4a: the coldest winter night averages −30 to −25 °F. The median last spring frost is May 7 and the first fall frost September 28.

Where ZIP 56541 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 7
First frostSep 28
2012 zone3b

Was 3b 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 4a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Flom, 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 Flom, MN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 7median — 50% chance of a later frost
Safe for tender plantsMay 24only 10% chance of frost after
First fall frostSeptember 28median — 10% chance by Sep 15
Growing season143 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 29 and returns around October 8.

From the NOAA station Mahnomen, MN — 13 miles away, elevation 1,211 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 56541

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 26 – Apr 9
SpinachSow outdoors · Mar 26 – Apr 16
Broccoli, cabbageStart indoors · Feb 26 – Mar 12
Broccoli, cabbageTransplant · Apr 16 – Apr 30
Onion setsPlant outdoors · Apr 9 – Apr 23
PotatoesPlant outdoors · Apr 16 – Apr 30
LettuceSow outdoors · Apr 9 – Apr 23
Carrots, beetsSow outdoors · Apr 16 – Apr 30
TomatoesStart indoors · Mar 12 – Mar 26
TomatoesTransplant · May 14 – May 28
Peppers, eggplantStart indoors · Feb 26 – Mar 12
Peppers, eggplantTransplant · May 21 – Jun 4
BeansSow outdoors · May 14 – May 28
Sweet cornSow outdoors · May 14 – May 28
Cucumbers, squashSow outdoors · May 14 – May 28
Fall lettuce, spinachSow outdoors · Aug 3 – Aug 17
GarlicPlant cloves · Sep 14 – Oct 19
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 7) and first fall frost (Sep 28) 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 56541 came on Apr 23 — about the same time as the 1991–2020 average (Apr 23).

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 Flom, MN.

Soil in Flom, MN

The soil mapped at the center of ZIP 56541 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, 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 56541; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Flom, MN

Summer high79 °Faverage high, July
Winter low−2 °Faverage low, January
Hot days5days a year at 90 °F or more
Freezing nights185nights a year at 32 °F or less
Growing degree days2,046base 50 °F — the season’s usable heat
Longest day15 h 55 mindaylight on June 21
Shortest day8 h 29 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation26 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 15 °F, low -2 °F 15°−2° JanFebruary: average high 21 °F, low 2 °F 21°2° FebMarch: average high 34 °F, low 15 °F 34°15° MarApril: average high 52 °F, low 30 °F 52°30° AprMay: average high 66 °F, low 43 °F 66°43° MayJune: average high 74 °F, low 54 °F 74°54° JunJuly: average high 79 °F, low 58 °F 79°58° JulAugust: average high 78 °F, low 55 °F 78°55° AugSeptember: average high 69 °F, low 47 °F 69°47° SepOctober: average high 54 °F, low 34 °F 54°34° OctNovember: average high 34 °F, low 20 °F 34°20° NovDecember: average high 22 °F, low 6 °F 22°6° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 0.73 in precipitation 0.7 JanFebruary: 0.63 in precipitation 0.6 FebMarch: 1.04 in precipitation 1.0 MarApril: 1.63 in precipitation 1.6 AprMay: 3.42 in precipitation 3.4 MayJune: 4.49 in precipitation 4.5 JunJuly: 3.67 in precipitation 3.7 JulAugust: 3.40 in precipitation 3.4 AugSeptember: 2.83 in precipitation 2.8 SepOctober: 2.44 in precipitation 2.4 OctNovember: 0.87 in precipitation 0.9 NovDecember: 0.83 in precipitation 0.8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Mahnomen, MN (13 mi away); precipitation: Twin Valley 0.1 Ne, MN (8 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 4a.

565844a
Twin Valley, MN · 6 mi
565854a
Ulen, MN · 8 mi
565524a
Hitterdal, MN · 14 mi
565914a
White Earth, MN · 14 mi
565194a
Borup, MN · 16 mi
565694a
Ogema, MN · 16 mi
565454a
Gary, MN · 16 mi
565214a
Callaway, MN · 16 mi

Minnesota planting zones →

Questions about 56541

What planting zone is ZIP code 56541?

ZIP code 56541 (Flom, 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 Flom, MN?

The median last spring frost (32 °F) near 56541 is May 7; after May 24 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Mahnomen station.

When is the first frost in Flom, MN?

The median first fall frost near 56541 is September 28, giving a median frost-free growing season of 143 days.

When should I plant tomatoes in 56541?

Start tomato seeds indoors around Mar 12 – Mar 26 and set transplants outside around May 14 – May 28, one to three weeks after the median last frost.

How much rain and snow does 56541 get?

About 26 inches of precipitation a year (NOAA 1991–2020 normals, Twin Valley 0.1 Ne station).

How hot do summers get in Flom, MN?

The average high peaks at 79 °F in July, with about 5 days a year at 90 °F or more.

What kind of soil does 56541 have?

The USDA soil survey maps Sverdrup at the center of ZIP 56541: sandy loam, well drained, pH about 7.0 (neutral).

Did spring come early in Flom, MN in 2026?

Spring leaf-out near 56541 came on Apr 23 in 2026, about the same as the 1991–2020 average (Apr 23), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Flom, MN?

Long-day onions: the longest day near 56541 is 15 h 55 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 56541 change?

Yes. The 2012 USDA map put 56541 in zone 3b; the 2023 map puts it in zone 4a. The newer map uses 1991–2020 data and more weather stations.