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

Planting zone for 58018 — Colfax, ND

ZIP code 58018 (Colfax, Richland County) is in USDA zone 4a: the coldest winter night averages −30 to −25 °F. The median last spring frost is May 6 and the first fall frost September 29.

Where ZIP 58018 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 6
First frostSep 29
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 Colfax, 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 Colfax, ND

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 6median — 50% chance of a later frost
Safe for tender plantsMay 19only 10% chance of frost after
First fall frostSeptember 29median — 10% chance by Sep 18
Growing season145 daysfrost-free, median

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

From the NOAA station Mc Leod 3 E, ND — 17 miles away, elevation 1,076 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 58018

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 25 – Apr 8
SpinachSow outdoors · Mar 25 – Apr 15
Broccoli, cabbageStart indoors · Feb 25 – Mar 11
Broccoli, cabbageTransplant · Apr 15 – Apr 29
Onion setsPlant outdoors · Apr 8 – Apr 22
PotatoesPlant outdoors · Apr 15 – Apr 29
LettuceSow outdoors · Apr 8 – Apr 22
Carrots, beetsSow outdoors · Apr 15 – Apr 29
TomatoesStart indoors · Mar 11 – Mar 25
TomatoesTransplant · May 13 – May 27
Peppers, eggplantStart indoors · Feb 25 – Mar 11
Peppers, eggplantTransplant · May 20 – Jun 3
BeansSow outdoors · May 13 – May 27
Sweet cornSow outdoors · May 13 – May 27
Cucumbers, squashSow outdoors · May 13 – May 27
Fall lettuce, spinachSow outdoors · Aug 4 – Aug 18
GarlicPlant cloves · Sep 15 – Oct 20
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 6) and first fall frost (Sep 29) 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 58018 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 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 Colfax, ND.

Soil in Colfax, ND

The soil mapped at the center of ZIP 58018 is Mantador — fine sandy loam, somewhat poorly drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding
pH7.6slightly alkaline; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter3%moderate
Hydrologic groupBwater soaks in moderately
Farmland classprime farmlandUSDA classification

Map unit: Mantador-Delamere-Elmville fine sandy loams, slightly saline, clayey substratum, 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 58018; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Colfax, ND

Summer high83 °Faverage high, July
Winter low−1 °Faverage low, January
Hot days12days a year at 90 °F or more
Freezing nights177nights a year at 32 °F or less
Growing degree days2,440base 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)
Precipitation25.2 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 19 °F, low -1 °F 19°−1° JanFebruary: average high 24 °F, low 3 °F 24°3° FebMarch: average high 38 °F, low 17 °F 38°17° MarApril: average high 55 °F, low 31 °F 55°31° AprMay: average high 69 °F, low 45 °F 69°45° MayJune: average high 78 °F, low 56 °F 78°56° JunJuly: average high 83 °F, low 60 °F 83°60° JulAugust: average high 81 °F, low 57 °F 81°57° AugSeptember: average high 73 °F, low 48 °F 73°48° SepOctober: average high 57 °F, low 34 °F 57°34° OctNovember: average high 39 °F, low 20 °F 39°20° NovDecember: average high 25 °F, low 6 °F 25°6° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 0.65 in precipitation 0.7 JanFebruary: 0.64 in precipitation 0.6 FebMarch: 1.14 in precipitation 1.1 MarApril: 1.95 in precipitation 1.9 AprMay: 3.38 in precipitation 3.4 MayJune: 4.11 in precipitation 4.1 JunJuly: 3.52 in precipitation 3.5 JulAugust: 2.85 in precipitation 2.9 AugSeptember: 2.86 in precipitation 2.9 SepOctober: 2.33 in precipitation 2.3 OctNovember: 0.85 in precipitation 0.8 NovDecember: 0.91 in precipitation 0.9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Mc Leod 3 E, ND (17 mi away); precipitation: Abercrombie 0.2 Nw, ND (7 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 4a.

580014a
Abercrombie, ND · 7 mi
580774a
Walcott, ND · 7 mi
580084a
Barney, ND · 10 mi
580614a
Mooreton, ND · 11 mi
580154a
Christine, ND · 11 mi
565534a
Kent, MN · 13 mi
580754a
Wahpeton, ND · 13 mi
565944a
Wolverton, MN · 14 mi

North Dakota planting zones →

Questions about 58018

What planting zone is ZIP code 58018?

ZIP code 58018 (Colfax, 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 Colfax, ND?

The median last spring frost (32 °F) near 58018 is May 6; after May 19 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Mc Leod 3 E station.

When is the first frost in Colfax, ND?

The median first fall frost near 58018 is September 29, giving a median frost-free growing season of 145 days.

When should I plant tomatoes in 58018?

Start tomato seeds indoors around Mar 11 – Mar 25 and set transplants outside around May 13 – May 27, one to three weeks after the median last frost.

How much rain and snow does 58018 get?

About 25.2 inches of precipitation a year (NOAA 1991–2020 normals, Abercrombie 0.2 Nw station).

How hot do summers get in Colfax, ND?

The average high peaks at 83 °F in July, with about 12 days a year at 90 °F or more.

What kind of soil does 58018 have?

The USDA soil survey maps Mantador at the center of ZIP 58018: fine sandy loam, somewhat poorly drained, pH about 7.6 (slightly alkaline).

Did spring come early in Colfax, ND in 2026?

Spring leaf-out near 58018 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 Colfax, ND?

Long-day onions: the longest day near 58018 is 15 h 49 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).