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

Planting zone for 59453 — Judith Gap, MT

ZIP code 59453 (Judith Gap, Wheatland County) is in USDA zone 4b: the coldest winter night averages −25 to −20 °F. The median last spring frost is June 1 and the first fall frost September 15.

Where ZIP 59453 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.

Zone4b−25 to −20 °F
Coldest night−31.7 to −28.9 °C
Last frostJun 1
First frostSep 15
2012 zone4a

Was 4a 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 4b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Judith Gap, MT…

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 Judith Gap, MT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostJune 1median — 50% chance of a later frost
Safe for tender plantsJune 16only 10% chance of frost after
First fall frostSeptember 15median — 10% chance by Aug 31
Growing season104 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 15 and returns around September 28.

From the NOAA station Judith Gap, MT — 4 miles away, elevation 4,629 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 59453

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 20 – May 4
SpinachSow outdoors · Apr 20 – May 11
Broccoli, cabbageStart indoors · Mar 23 – Apr 6
Broccoli, cabbageTransplant · May 11 – May 25
Onion setsPlant outdoors · May 4 – May 18
PotatoesPlant outdoors · May 11 – May 25
LettuceSow outdoors · May 4 – May 18
Carrots, beetsSow outdoors · May 11 – May 25
TomatoesStart indoors · Apr 6 – Apr 20
TomatoesTransplant · Jun 8 – Jun 22
Peppers, eggplantStart indoors · Mar 23 – Apr 6
Peppers, eggplantTransplant · Jun 15 – Jun 29
BeansSow outdoors · Jun 8 – Jun 22
Sweet cornSow outdoors · Jun 8 – Jun 22
Cucumbers, squashSow outdoors · Jun 8 – Jun 22
Fall lettuce, spinachSow outdoors · Jul 21 – Aug 4
GarlicPlant cloves · Sep 1 – Oct 6
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jun 1) and first fall frost (Sep 15) 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 59453 came on Mar 21 — 27 days earlier than the 1991–2020 average (Apr 17).

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 4b in Montana

506 plants native to the lower 48 states, recorded in Montana, and rated by the USDA to survive −25 °F or colder — the bottom of zone 4b. Each links to its USDA PLANTS profile.

Trees 23

American elm120 ft · blooms early spring · medium shade tolerance · to −46 °Fbalsam poplar80 ft · blooms late spring · high shade tolerance · to −79 °Fblack locust60 ft · blooms spring · high shade tolerance · to −37 °Fboxelder60 ft · blooms early spring · low shade tolerance · to −46 °FDouglas-fir200 ft · blooms mid spring · medium shade tolerance · to −33 °Feastern cottonwood190 ft · blooms spring · high shade tolerance · to −43 °F

Shrubs 87

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °Falderleaf mountain mahogany15 ft · blooms late spring · medium shade tolerance · to −41 °Falpine laurel1 ft · blooms late spring · low shade tolerance · to −28 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican plum24 ft · blooms mid spring · high shade tolerance · to −38 °Fantelope bitterbrush6 ft · blooms early spring · medium shade tolerance · to −36 °F

Wildflowers & perennials 229

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °Falpine mountainsorrel1 ft · blooms mid summer · medium shade tolerance · to −43 °Falpine sweetvetch2 ft · blooms early summer · high shade tolerance · to −62 °FAmerican alpine speedwell1 ft · blooms summer · medium shade tolerance · to −28 °FAmerican bistort1.5 ft · blooms mid spring · high shade tolerance · to −38 °F

Grasses 155

Alaska oniongrass3 ft · blooms mid spring · low shade tolerance · to −33 °Falkali cordgrass3 ft · blooms late summer · high shade tolerance · to −38 °Falkali sacaton3 ft · blooms mid summer · high shade tolerance · to −38 °FAlpine Meadow-Foxtail0.5 ft · blooms mid spring · medium shade tolerance · to −33 °Falpine timothy1.4 ft · blooms late spring · medium shade tolerance · to −43 °Fanalogue sedge1.5 ft · blooms late spring · medium shade tolerance · to −38 °F

Vines 3

American bittersweet15 ft · blooms spring · low 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 Judith Gap, MT.

Soil in Judith Gap, MT

The soil mapped at the center of ZIP 59453 is Macar — loam, well drained.

TextureLoama good balance for most vegetables
pH7.6slightly alkaline; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2%moderate
Hydrologic groupBwater soaks in moderately
Farmland classprime farmlandUSDA classification

Map unit: Macar loam, 4 to 8 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 59453; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Judith Gap, MT

Summer high80 °Faverage high, August
Winter low12 °Faverage low, January
Hot days17days a year at 90 °F or more
Freezing nights192nights a year at 32 °F or less
Growing degree days1,411base 50 °F — the season’s usable heat
Longest day15 h 51 mindaylight on June 21
Shortest day8 h 33 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation15.9 inper year, rain and melted snow
Snowfall28 inper year; 34 days with snow on the ground

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 34 °F, low 12 °F 34°12° JanFebruary: average high 34 °F, low 13 °F 34°13° FebMarch: average high 42 °F, low 20 °F 42°20° MarApril: average high 51 °F, low 27 °F 51°27° AprMay: average high 60 °F, low 36 °F 60°36° MayJune: average high 68 °F, low 44 °F 68°44° JunJuly: average high 79 °F, low 50 °F 79°50° JulAugust: average high 80 °F, low 49 °F 80°49° AugSeptember: average high 69 °F, low 40 °F 69°40° SepOctober: average high 54 °F, low 30 °F 54°30° OctNovember: average high 42 °F, low 21 °F 42°21° NovDecember: average high 33 °F, low 12 °F 33°12° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″January: 0.43 in precipitation, 4.5 in snowfall 0.4❄5 JanFebruary: 0.45 in precipitation, 6.7 in snowfall 0.5❄7 FebMarch: 0.64 in precipitation, 3.6 in snowfall 0.6❄4 MarApril: 1.75 in precipitation, 2.8 in snowfall 1.8❄3 AprMay: 3.26 in precipitation, 0.4 in snowfall 3.3 MayJune: 3.03 in precipitation 3.0 JunJuly: 1.73 in precipitation 1.7 JulAugust: 1.49 in precipitation 1.5 AugSeptember: 1.36 in precipitation, 0.2 in snowfall 1.4 SepOctober: 0.89 in precipitation, 1.8 in snowfall 0.9❄2 OctNovember: 0.51 in precipitation, 3.7 in snowfall 0.5❄4 NovDecember: 0.38 in precipitation, 3.8 in snowfall 0.4❄4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Judith Gap, MT (4 mi away); precipitation: Judith Gap, MT (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 4b.

594184b
Buffalo, MT · 14 mi
594644b
Moore, MT · 14 mi
590364b
Harlowton, MT · 16 mi
590784b
Shawmut, MT · 18 mi
594524b
Hobson, MT · 25 mi
590744b
Ryegate, MT · 27 mi
594414b
Forest Grove, MT · 32 mi
590854b
Two Dot, MT · 33 mi

Montana planting zones →

Questions about 59453

What planting zone is ZIP code 59453?

ZIP code 59453 (Judith Gap, MT) is in USDA hardiness zone 4b on the 2023 map: the coldest night of an average winter reaches −25 to −20 °F (−31.7 to −28.9 °C).

When is the last frost in Judith Gap, MT?

The median last spring frost (32 °F) near 59453 is June 1; after June 16 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Judith Gap station.

When is the first frost in Judith Gap, MT?

The median first fall frost near 59453 is September 15, giving a median frost-free growing season of 104 days.

When should I plant tomatoes in 59453?

Start tomato seeds indoors around Apr 6 – Apr 20 and set transplants outside around Jun 8 – Jun 22, one to three weeks after the median last frost.

How much rain and snow does 59453 get?

About 15.9 inches of precipitation a year and 28 inches of snowfall (NOAA 1991–2020 normals, Judith Gap station).

How hot do summers get in Judith Gap, MT?

The average high peaks at 80 °F in August, with about 17 days a year at 90 °F or more.

What kind of soil does 59453 have?

The USDA soil survey maps Macar at the center of ZIP 59453: loam, well drained, pH about 7.6 (slightly alkaline).

Did spring come early in Judith Gap, MT in 2026?

Spring leaf-out near 59453 came on Mar 21 in 2026, 27 days earlier than the 1991–2020 average (Apr 17), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Judith Gap, MT?

Long-day onions: the longest day near 59453 is 15 h 51 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 59453 change?

Yes. The 2012 USDA map put 59453 in zone 4a; the 2023 map puts it in zone 4b. The newer map uses 1991–2020 data and more weather stations.