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

Planting zone for 59718 — Bozeman, MT

ZIP code 59718 (Bozeman, Gallatin County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is May 23 and the first fall frost September 23.

Where ZIP 59718 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.

Zone5a−20 to −15 °F
Coldest night−28.9 to −26.1 °C
Last frostMay 23
First frostSep 23
2012 zone4b

Was 4b 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 5a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Bozeman, 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 Bozeman, MT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 23median — 50% chance of a later frost
Safe for tender plantsJune 12only 10% chance of frost after
First fall frostSeptember 23median — 10% chance by Sep 4
Growing season123 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 2 and returns around October 3.

From the NOAA station Bozeman 6 W Exp Farm, MT — 2 miles away, elevation 4,774 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 59718

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 11 – Apr 25
SpinachSow outdoors · Apr 11 – May 2
Broccoli, cabbageStart indoors · Mar 14 – Mar 28
Broccoli, cabbageTransplant · May 2 – May 16
Onion setsPlant outdoors · Apr 25 – May 9
PotatoesPlant outdoors · May 2 – May 16
LettuceSow outdoors · Apr 25 – May 9
Carrots, beetsSow outdoors · May 2 – May 16
TomatoesStart indoors · Mar 28 – Apr 11
TomatoesTransplant · May 30 – Jun 13
Peppers, eggplantStart indoors · Mar 14 – Mar 28
Peppers, eggplantTransplant · Jun 6 – Jun 20
BeansSow outdoors · May 30 – Jun 13
Sweet cornSow outdoors · May 30 – Jun 13
Cucumbers, squashSow outdoors · May 30 – Jun 13
Fall lettuce, spinachSow outdoors · Jul 29 – Aug 12
GarlicPlant cloves · Sep 9 – Oct 14
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 23) and first fall frost (Sep 23) 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 59718 came on Mar 19 — 28 days earlier than the 1991–2020 average (Apr 16).

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 5a in Montana

548 plants native to the lower 48 states, recorded in Montana, and rated by the USDA to survive −20 °F or colder — the bottom of zone 5a. Each links to its USDA PLANTS profile.

Trees 26

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 96

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 253

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 161

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 Bozeman, MT.

Soil in Bozeman, MT

The soil mapped at the center of ZIP 59718 is Amsterdam — silt loam, well drained.

TextureSilt loama good balance for most vegetables
pH7.0neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3%moderate
Hydrologic groupCwater soaks in slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Amsterdam-Quagle silt loams, 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 59718; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Bozeman, MT

Summer high83 °Faverage high, July
Winter low15 °Faverage low, January
Hot days13days a year at 90 °F or more
Freezing nights180nights a year at 32 °F or less
Growing degree days1,751base 50 °F — the season’s usable heat
Longest day15 h 42 mindaylight on June 21
Shortest day8 h 41 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation15.8 inper year, rain and melted snow

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 34 °F, low 15 °F 34°15° JanFebruary: average high 37 °F, low 17 °F 37°17° FebMarch: average high 47 °F, low 25 °F 47°25° MarApril: average high 55 °F, low 31 °F 55°31° AprMay: average high 65 °F, low 39 °F 65°39° MayJune: average high 72 °F, low 45 °F 72°45° JunJuly: average high 83 °F, low 51 °F 83°51° JulAugust: average high 82 °F, low 50 °F 82°50° AugSeptember: average high 72 °F, low 42 °F 72°42° SepOctober: average high 58 °F, low 33 °F 58°33° OctNovember: average high 43 °F, low 22 °F 43°22° NovDecember: average high 34 °F, low 15 °F 34°15° Dec

Precipitation by month inches

0″1″2″3″January: 0.52 in precipitation 0.5 JanFebruary: 0.51 in precipitation 0.5 FebMarch: 0.96 in precipitation 1.0 MarApril: 1.89 in precipitation 1.9 AprMay: 2.69 in precipitation 2.7 MayJune: 2.80 in precipitation 2.8 JunJuly: 1.22 in precipitation 1.2 JulAugust: 1.08 in precipitation 1.1 AugSeptember: 1.31 in precipitation 1.3 SepOctober: 1.41 in precipitation 1.4 OctNovember: 0.85 in precipitation 0.8 NovDecember: 0.60 in precipitation 0.6 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Bozeman 6 W Exp Farm, MT (2 mi away); precipitation: Bozeman 6 W Exp Farm, MT (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 5a.

597725a
Bozeman, MT · 5 mi
597715a
Bozeman, MT · 6 mi
597195a
Bozeman, MT · 13 mi
597415a
Manhattan, MT · 13 mi
597155a
Bozeman, MT · 13 mi
597455a
Norris, MT · 22 mi
597605a
Willow Creek, MT · 22 mi
597145a
Belgrade, MT · 23 mi

All 5 ZIP codes in Bozeman → · Montana planting zones →

Questions about 59718

What planting zone is ZIP code 59718?

ZIP code 59718 (Bozeman, MT) is in USDA hardiness zone 5a on the 2023 map: the coldest night of an average winter reaches −20 to −15 °F (−28.9 to −26.1 °C).

When is the last frost in Bozeman, MT?

The median last spring frost (32 °F) near 59718 is May 23; after June 12 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Bozeman 6 W Exp Farm station.

When is the first frost in Bozeman, MT?

The median first fall frost near 59718 is September 23, giving a median frost-free growing season of 123 days.

When should I plant tomatoes in 59718?

Start tomato seeds indoors around Mar 28 – Apr 11 and set transplants outside around May 30 – Jun 13, one to three weeks after the median last frost.

How much rain and snow does 59718 get?

About 15.8 inches of precipitation a year (NOAA 1991–2020 normals, Bozeman 6 W Exp Farm station).

How hot do summers get in Bozeman, MT?

The average high peaks at 83 °F in July, with about 13 days a year at 90 °F or more.

What kind of soil does 59718 have?

The USDA soil survey maps Amsterdam at the center of ZIP 59718: silt loam, well drained, pH about 7.0 (neutral).

Did spring come early in Bozeman, MT in 2026?

Spring leaf-out near 59718 came on Mar 19 in 2026, 28 days earlier than the 1991–2020 average (Apr 16), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Bozeman, MT?

Long-day onions: the longest day near 59718 is 15 h 42 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 59718 change?

Yes. The 2012 USDA map put 59718 in zone 4b; the 2023 map puts it in zone 5a. The newer map uses 1991–2020 data and more weather stations.