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

Planting zone for 59648 — Wolf Creek, MT

ZIP code 59648 (Wolf Creek, Lewis and Clark County) is in USDA zone 4b: the coldest winter night averages −25 to −20 °F. The median last spring frost is May 21 and the first fall frost September 15.

Where ZIP 59648 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 frostMay 21
First frostSep 15
2012 zone4b

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 4b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Wolf Creek, 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 Wolf Creek, MT

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 8only 10% chance of frost after
First fall frostSeptember 15median — 10% chance by Aug 30
Growing season115 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 7 and returns around September 28.

From the NOAA station Rogers Pass 9 Nne, MT — 8 miles away, elevation 4,200 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 59648

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 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 (May 21) 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 59648 came on Apr 6 — 18 days earlier than the 1991–2020 average (Apr 24).

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 Wolf Creek, MT.

Soil in Wolf Creek, MT

The soil mapped at the center of ZIP 59648 is Tolex — slightly decomposed plant material, well drained.

TextureSlightly decomposed plant materialtop layer
pH6.5neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter50%high
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Tolex-Mocmont-Rock outcrop complex, 25 to 60 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 59648; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Wolf Creek, MT

Summer high82 °Faverage high, July
Winter low16 °Faverage low, February
Hot days12days a year at 90 °F or more
Freezing nights169nights a year at 32 °F or less
Growing degree days1,619base 50 °F — the season’s usable heat
Longest day15 h 55 mindaylight on June 21
Shortest day8 h 30 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation17.1 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 36 °F, low 17 °F 36°17° JanFebruary: average high 37 °F, low 16 °F 37°16° FebMarch: average high 45 °F, low 23 °F 45°23° MarApril: average high 53 °F, low 30 °F 53°30° AprMay: average high 62 °F, low 38 °F 62°38° MayJune: average high 71 °F, low 46 °F 71°46° JunJuly: average high 82 °F, low 51 °F 82°51° JulAugust: average high 81 °F, low 49 °F 81°49° AugSeptember: average high 70 °F, low 41 °F 70°41° SepOctober: average high 55 °F, low 32 °F 55°32° OctNovember: average high 42 °F, low 25 °F 42°25° NovDecember: average high 34 °F, low 18 °F 34°18° Dec

Precipitation by month inches

0″1″2″3″4″January: 0.64 in precipitation 0.6 JanFebruary: 0.75 in precipitation 0.8 FebMarch: 0.88 in precipitation 0.9 MarApril: 1.77 in precipitation 1.8 AprMay: 2.99 in precipitation 3.0 MayJune: 3.06 in precipitation 3.1 JunJuly: 1.23 in precipitation 1.2 JulAugust: 1.24 in precipitation 1.2 AugSeptember: 1.65 in precipitation 1.6 SepOctober: 1.37 in precipitation 1.4 OctNovember: 0.75 in precipitation 0.8 NovDecember: 0.76 in precipitation 0.8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Rogers Pass 9 Nne, MT (8 mi away); precipitation: Rogers Pass 9 Nne, MT (8 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 4b.

596334b
Canyon Creek, MT · 20 mi
596404b
Marysville, MT · 24 mi
594214b
Cascade, MT · 24 mi
594774b
Simms, MT · 26 mi
596394b
Lincoln, MT · 27 mi
596024b
Helena, MT · 29 mi
596044b
Helena, MT · 31 mi
596364b
Fort Harrison, MT · 33 mi

Montana planting zones →

Questions about 59648

What planting zone is ZIP code 59648?

ZIP code 59648 (Wolf Creek, 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 Wolf Creek, MT?

The median last spring frost (32 °F) near 59648 is May 21; after June 8 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Rogers Pass 9 Nne station.

When is the first frost in Wolf Creek, MT?

The median first fall frost near 59648 is September 15, giving a median frost-free growing season of 115 days.

When should I plant tomatoes in 59648?

Start tomato seeds indoors around Mar 26 – Apr 9 and set transplants outside around May 28 – Jun 11, one to three weeks after the median last frost.

How much rain and snow does 59648 get?

About 17.1 inches of precipitation a year (NOAA 1991–2020 normals, Rogers Pass 9 Nne station).

How hot do summers get in Wolf Creek, MT?

The average high peaks at 82 °F in July, with about 12 days a year at 90 °F or more.

What kind of soil does 59648 have?

The USDA soil survey maps Tolex at the center of ZIP 59648: slightly decomposed plant material, well drained, pH about 6.5 (neutral).

Did spring come early in Wolf Creek, MT in 2026?

Spring leaf-out near 59648 came on Apr 6 in 2026, 18 days earlier than the 1991–2020 average (Apr 24), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Wolf Creek, MT?

Long-day onions: the longest day near 59648 is 15 h 55 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).