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

Planting zone for 58566 — Saint Anthony, ND

ZIP code 58566 (Saint Anthony, Morton County) is in USDA zone 4a: the coldest winter night averages −30 to −25 °F. The median last spring frost is May 12 and the first fall frost September 24.

Where ZIP 58566 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 12
First frostSep 24
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 Saint Anthony, ND…

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 Saint Anthony, ND

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 12median — 50% chance of a later frost
Safe for tender plantsMay 27only 10% chance of frost after
First fall frostSeptember 24median — 10% chance by Sep 11
Growing season134 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 1 and returns around October 4.

From the NOAA station Breien, ND — 14 miles away, elevation 1,719 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 58566

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 31 – Apr 14
SpinachSow outdoors · Mar 31 – Apr 21
Broccoli, cabbageStart indoors · Mar 3 – Mar 17
Broccoli, cabbageTransplant · Apr 21 – May 5
Onion setsPlant outdoors · Apr 14 – Apr 28
PotatoesPlant outdoors · Apr 21 – May 5
LettuceSow outdoors · Apr 14 – Apr 28
Carrots, beetsSow outdoors · Apr 21 – May 5
TomatoesStart indoors · Mar 17 – Mar 31
TomatoesTransplant · May 19 – Jun 2
Peppers, eggplantStart indoors · Mar 3 – Mar 17
Peppers, eggplantTransplant · May 26 – Jun 9
BeansSow outdoors · May 19 – Jun 2
Sweet cornSow outdoors · May 19 – Jun 2
Cucumbers, squashSow outdoors · May 19 – Jun 2
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 12) 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 58566 came on Apr 16 — 3 days earlier than the 1991–2020 average (Apr 19).

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 North Dakota

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

Trees 21

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °Fbalsam poplar80 ft · blooms late spring · high shade tolerance · to −79 °Fbigtooth aspen65 ft · blooms mid spring · high shade tolerance · to −43 °Fblack ash65 ft · blooms early spring · high shade tolerance · to −47 °Fblack locust60 ft · blooms spring · high shade tolerance · to −37 °F

Shrubs 56

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican plum24 ft · blooms mid spring · high shade tolerance · to −38 °Fbeaked hazelnut15 ft · blooms early spring · low shade tolerance · to −47 °Fbig sagebrush4 ft · blooms mid summer · high shade tolerance · to −43 °F

Wildflowers & perennials 146

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine sweetvetch2 ft · blooms early summer · high shade tolerance · to −62 °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 speedwell0.8 ft · blooms mid summer · low shade tolerance · to −38 °F

Grasses 110

alkali cordgrass3 ft · blooms late summer · high shade tolerance · to −38 °Falkali sacaton3 ft · blooms mid summer · high shade tolerance · to −38 °Fanalogue sedge1.5 ft · blooms late spring · medium 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 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °F

Vines 4

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 °Fwestern white clematis1 ft · blooms mid summer · medium shade tolerance · to −38 °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 Saint Anthony, ND.

Soil in Saint Anthony, ND

The soil mapped at the center of ZIP 58566 is Reeder — loam, well drained.

TextureLoama good balance for most vegetables
pH7.0neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2%moderate
Hydrologic groupCwater soaks in slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Reeder-Farnuf loams, 3 to 6 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 58566; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Saint Anthony, ND

Summer high86 °Faverage high, July
Winter low1 °Faverage low, January
Hot days26days a year at 90 °F or more
Freezing nights192nights a year at 32 °F or less
Growing degree days2,360base 50 °F — the season’s usable heat
Longest day15 h 50 mindaylight on June 21
Shortest day8 h 34 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation19.1 inper year, rain and melted snow
Snowfall51 inper year; 92 days with snow on the ground

Average high and low, by month

−10°0°10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 25 °F, low 1 °F 25°1° JanFebruary: average high 30 °F, low 6 °F 30°6° FebMarch: average high 43 °F, low 18 °F 43°18° MarApril: average high 58 °F, low 29 °F 58°29° AprMay: average high 70 °F, low 42 °F 70°42° MayJune: average high 79 °F, low 52 °F 79°52° JunJuly: average high 86 °F, low 58 °F 86°58° JulAugust: average high 86 °F, low 54 °F 86°54° AugSeptember: average high 75 °F, low 44 °F 75°44° SepOctober: average high 60 °F, low 31 °F 60°31° OctNovember: average high 42 °F, low 18 °F 42°18° NovDecember: average high 29 °F, low 6 °F 29°6° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″January: 0.48 in precipitation, 8.9 in snowfall 0.5❄9 JanFebruary: 0.52 in precipitation, 7.5 in snowfall 0.5❄8 FebMarch: 0.84 in precipitation, 8.5 in snowfall 0.8❄9 MarApril: 1.34 in precipitation, 4.6 in snowfall 1.3❄5 AprMay: 2.50 in precipitation, 0.4 in snowfall 2.5 MayJune: 3.36 in precipitation 3.4 JunJuly: 3.07 in precipitation 3.1 JulAugust: 2.50 in precipitation 2.5 AugSeptember: 1.72 in precipitation 1.7 SepOctober: 1.43 in precipitation, 2.5 in snowfall 1.4❄3 OctNovember: 0.69 in precipitation, 8 in snowfall 0.7❄8 NovDecember: 0.60 in precipitation, 10.1 in snowfall 0.6❄10 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Breien, ND (14 mi away); precipitation: Bismarck, ND (15 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 4a.

585544a
Mandan, ND · 12 mi
585704a
Solen, ND · 14 mi
585044a
Bismarck, ND · 16 mi
585064a
Bismarck, ND · 17 mi
585074a
Bismarck, ND · 17 mi
585354a
Flasher, ND · 18 mi
585054a
Bismarck, ND · 18 mi
585014a
Bismarck, ND · 19 mi

North Dakota planting zones →

Questions about 58566

What planting zone is ZIP code 58566?

ZIP code 58566 (Saint Anthony, ND) 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 Saint Anthony, ND?

The median last spring frost (32 °F) near 58566 is May 12; after May 27 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Breien station.

When is the first frost in Saint Anthony, ND?

The median first fall frost near 58566 is September 24, giving a median frost-free growing season of 134 days.

When should I plant tomatoes in 58566?

Start tomato seeds indoors around Mar 17 – Mar 31 and set transplants outside around May 19 – Jun 2, one to three weeks after the median last frost.

How much rain and snow does 58566 get?

About 19.1 inches of precipitation a year and 51 inches of snowfall (NOAA 1991–2020 normals, Bismarck station).

How hot do summers get in Saint Anthony, ND?

The average high peaks at 86 °F in July, with about 26 days a year at 90 °F or more.

What kind of soil does 58566 have?

The USDA soil survey maps Reeder at the center of ZIP 58566: loam, well drained, pH about 7.0 (neutral).

Did spring come early in Saint Anthony, ND in 2026?

Spring leaf-out near 58566 came on Apr 16 in 2026, 3 days earlier than the 1991–2020 average (Apr 19), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Saint Anthony, ND?

Long-day onions: the longest day near 58566 is 15 h 50 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).