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

Planting zone for 58856 — Zahl, ND

ZIP code 58856 (Zahl, Williams County) is in USDA zone 4a: the coldest winter night averages −30 to −25 °F. The median last spring frost is May 19 and the first fall frost September 17.

Where ZIP 58856 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 19
First frostSep 17
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 Zahl, 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 Zahl, ND

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 19median — 50% chance of a later frost
Safe for tender plantsMay 31only 10% chance of frost after
First fall frostSeptember 17median — 10% chance by Sep 4
Growing season121 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 10 and returns around September 26.

From the NOAA station Fortuna 1 W, ND — 22 miles away, elevation 2,349 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 58856

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 7 – Apr 21
SpinachSow outdoors · Apr 7 – Apr 28
Broccoli, cabbageStart indoors · Mar 10 – Mar 24
Broccoli, cabbageTransplant · Apr 28 – May 12
Onion setsPlant outdoors · Apr 21 – May 5
PotatoesPlant outdoors · Apr 28 – May 12
LettuceSow outdoors · Apr 21 – May 5
Carrots, beetsSow outdoors · Apr 28 – May 12
TomatoesStart indoors · Mar 24 – Apr 7
TomatoesTransplant · May 26 – Jun 9
Peppers, eggplantStart indoors · Mar 10 – Mar 24
Peppers, eggplantTransplant · Jun 2 – Jun 16
BeansSow outdoors · May 26 – Jun 9
Sweet cornSow outdoors · May 26 – Jun 9
Cucumbers, squashSow outdoors · May 26 – Jun 9
Fall lettuce, spinachSow outdoors · Jul 23 – Aug 6
GarlicPlant cloves · Sep 3 – Oct 8
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 19) and first fall frost (Sep 17) 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 58856 came on Apr 21 — 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 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 Zahl, ND.

Soil in Zahl, ND

The soil mapped at the center of ZIP 58856 is Williams — loam, well drained.

TextureLoama good balance for most vegetables
pH7.2neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter4%moderate
Hydrologic groupCwater soaks in slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Williams-Bowbells 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 58856; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Zahl, ND

Summer high80 °Faverage high, July
Winter low−2 °Faverage low, January
Hot days10days a year at 90 °F or more
Freezing nights204nights a year at 32 °F or less
Growing degree days1,744base 50 °F — the season’s usable heat
Longest day16 h 08 mindaylight on June 21
Shortest day8 h 17 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation15.3 inper year, rain and melted snow
Snowfall37 inper year

Average high and low, by month

−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 17 °F, low -2 °F 17°−2° JanFebruary: average high 21 °F, low 2 °F 21°2° FebMarch: average high 34 °F, low 14 °F 34°14° MarApril: average high 52 °F, low 27 °F 52°27° AprMay: average high 65 °F, low 39 °F 65°39° MayJune: average high 73 °F, low 49 °F 73°49° JunJuly: average high 80 °F, low 54 °F 80°54° JulAugust: average high 80 °F, low 52 °F 80°52° AugSeptember: average high 69 °F, low 41 °F 69°41° SepOctober: average high 53 °F, low 28 °F 53°28° OctNovember: average high 35 °F, low 15 °F 35°15° NovDecember: average high 22 °F, low 3 °F 22°3° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″January: 0.62 in precipitation, 6.6 in snowfall 0.6❄7 JanFebruary: 0.46 in precipitation, 5.7 in snowfall 0.5❄6 FebMarch: 0.62 in precipitation, 7 in snowfall 0.6❄7 MarApril: 1.15 in precipitation, 3.4 in snowfall 1.1❄3 AprMay: 2.06 in precipitation, 0.9 in snowfall 2.1❄1 MayJune: 3.30 in precipitation 3.3 JunJuly: 2.43 in precipitation 2.4 JulAugust: 1.46 in precipitation 1.5 AugSeptember: 1.18 in precipitation 1.2 SepOctober: 1.03 in precipitation, 2.2 in snowfall 1.0❄2 OctNovember: 0.54 in precipitation, 4.3 in snowfall 0.5❄4 NovDecember: 0.48 in precipitation, 6.4 in snowfall 0.5❄6 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Fortuna 1 W, ND (22 mi away); precipitation: Fortuna 1 W, ND (22 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

5 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

588453b
Grenora, ND · 9 mi
588303b
Alamo, ND · 12 mi
592193b
Dagmar, MT · 19 mi
588443b
Fortuna, ND · 20 mi
588334a
Ambrose, ND · 22 mi
588014a
Williston, ND · 25 mi
587953b
Wildrose, ND · 27 mi
587304a
Crosby, ND · 27 mi

North Dakota planting zones →

Questions about 58856

What planting zone is ZIP code 58856?

ZIP code 58856 (Zahl, 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 Zahl, ND?

The median last spring frost (32 °F) near 58856 is May 19; after May 31 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Fortuna 1 W station.

When is the first frost in Zahl, ND?

The median first fall frost near 58856 is September 17, giving a median frost-free growing season of 121 days.

When should I plant tomatoes in 58856?

Start tomato seeds indoors around Mar 24 – Apr 7 and set transplants outside around May 26 – Jun 9, one to three weeks after the median last frost.

How much rain and snow does 58856 get?

About 15.3 inches of precipitation a year and 37 inches of snowfall (NOAA 1991–2020 normals, Fortuna 1 W station).

How hot do summers get in Zahl, ND?

The average high peaks at 80 °F in July, with about 10 days a year at 90 °F or more.

What kind of soil does 58856 have?

The USDA soil survey maps Williams at the center of ZIP 58856: loam, well drained, pH about 7.2 (neutral).

Did spring come early in Zahl, ND in 2026?

Spring leaf-out near 58856 came on Apr 21 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 Zahl, ND?

Long-day onions: the longest day near 58856 is 16 h 08 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 58856 change?

Yes. The 2012 USDA map put 58856 in zone 3b; the 2023 map puts it in zone 4a. The newer map uses 1991–2020 data and more weather stations.