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

Planting zone for Williston, ND

Williston, ND is in USDA zone 4a across its 3 ZIP codes. The median last spring frost is May 21 and the first fall frost September 21.

Williston on the zone map

Outlined: its 1 ZIP code areas · 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
ZIP codes3
Last frostMay 21
First frostSep 21
Growing season123 days

4a 3 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Williston, 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 Williston, ND

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 21median — 50% chance of a later frost
Safe for tender plantsJune 3only 10% chance of frost after
First fall frostSeptember 21median — 10% chance by Sep 9
Growing season123 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 11 and returns around September 28.

From the NOAA station Williston Sloulin Intl Airport, ND, elevation 1,903 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 Williston

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 9 – Apr 23
SpinachSow outdoors · Apr 9 – Apr 30
Broccoli, cabbageStart indoors · Mar 12 – Mar 26
Broccoli, cabbageTransplant · Apr 30 – May 14
Onion setsPlant outdoors · Apr 23 – May 7
PotatoesPlant outdoors · Apr 30 – May 14
LettuceSow outdoors · Apr 23 – May 7
Carrots, beetsSow outdoors · Apr 30 – May 14
TomatoesStart indoors · Mar 26 – Apr 9
TomatoesTransplant · May 28 – Jun 11
Peppers, eggplantStart indoors · Mar 12 – Mar 26
Peppers, eggplantTransplant · Jun 4 – Jun 18
BeansSow outdoors · May 28 – Jun 11
Sweet cornSow outdoors · May 28 – Jun 11
Cucumbers, squashSow outdoors · May 28 – Jun 11
Fall lettuce, spinachSow outdoors · Jul 27 – Aug 10
GarlicPlant cloves · Sep 7 – Oct 12
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 21) and first fall frost (Sep 21) 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 58802 came on Apr 20 — about the same time as 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 Williston, ND.

Soil in Williston, ND

The soil mapped at the center of ZIP 58802 is Tally — fine sandy loam, well drained.

TextureFine sandy 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%moderate
Hydrologic groupAwater soaks in fast
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Tally-Parshall fine sandy loams, 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 58802; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Williston, ND

Summer high85 °Faverage high, July
Winter low1 °Faverage low, January
Hot days21days a year at 90 °F or more
Freezing nights191nights a year at 32 °F or less
Growing degree days2,149base 50 °F — the season’s usable heat
Longest day16 h 04 mindaylight on June 21
Shortest day8 h 20 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation15.1 inper year, rain and melted snow
Snowfall48 inper year; 97 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 22 °F, low 1 °F 22°1° JanFebruary: average high 27 °F, low 6 °F 27°6° FebMarch: average high 40 °F, low 18 °F 40°18° MarApril: average high 56 °F, low 29 °F 56°29° AprMay: average high 67 °F, low 40 °F 67°40° MayJune: average high 77 °F, low 50 °F 77°50° JunJuly: average high 85 °F, low 56 °F 85°56° JulAugust: average high 84 °F, low 54 °F 84°54° AugSeptember: average high 73 °F, low 44 °F 73°44° SepOctober: average high 56 °F, low 30 °F 56°30° OctNovember: average high 38 °F, low 17 °F 38°17° NovDecember: average high 26 °F, low 6 °F 26°6° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″January: 0.56 in precipitation, 11.2 in snowfall 0.6❄11 JanFebruary: 0.48 in precipitation, 6.7 in snowfall 0.5❄7 FebMarch: 0.63 in precipitation, 6.4 in snowfall 0.6❄6 MarApril: 1.05 in precipitation, 3.7 in snowfall 1.1❄4 AprMay: 2.10 in precipitation, 0.9 in snowfall 2.1❄1 MayJune: 2.64 in precipitation 2.6 JunJuly: 2.48 in precipitation 2.5 JulAugust: 1.57 in precipitation 1.6 AugSeptember: 1.36 in precipitation 1.4 SepOctober: 0.94 in precipitation, 2.6 in snowfall 0.9❄3 OctNovember: 0.67 in precipitation, 6.3 in snowfall 0.7❄6 NovDecember: 0.63 in precipitation, 10.4 in snowfall 0.6❄10 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Williston Sloulin Intl Airport, ND (within 1 mile); precipitation: Williston Sloulin Intl Airport, ND (within 1 mile). Daylight is calculated from latitude.

ZIP codes in Williston

588014a
−30 to −25 °F
588024a
−30 to −25 °F
588034a
−30 to −25 °F

North Dakota planting zones →

Questions about Williston

What planting zone is Williston, ND?

Williston, ND is in USDA hardiness zone 4a on the 2023 map (4a: −30 to −25 °F).

When is the last frost in Williston, ND?

The median last spring frost is May 21 and the median first fall frost is September 21 (NOAA 1991–2020 normals, Williston Sloulin Intl Airport station).

When can I plant a garden in Williston, ND?

Cool-season crops like peas and spinach go in around Apr 9 – Apr 30; tomatoes, peppers, beans and squash after about May 28, once frost risk has passed.

What kind of onions grow in Williston, ND?

Long-day onions: the longest day is 16 h 04 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

How much rain and snow does Williston, ND get?

About 15.1 inches of precipitation a year and 48 inches of snowfall (NOAA 1991–2020 normals).