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

Planting zone for 59076 — Sanders, MT

ZIP code 59076 (Sanders, Treasure County) is in USDA zone 4b: the coldest winter night averages −25 to −20 °F. The median last spring frost is May 10 and the first fall frost September 29.

Where ZIP 59076 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 10
First frostSep 29
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 Sanders, 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 Sanders, MT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 10median — 50% chance of a later frost
Safe for tender plantsMay 22only 10% chance of frost after
First fall frostSeptember 29median — 10% chance by Sep 15
Growing season141 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 30 and returns around October 7.

From the NOAA station Hysham, MT — 7 miles away, elevation 2,671 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 59076

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 29 – Apr 12
SpinachSow outdoors · Mar 29 – Apr 19
Broccoli, cabbageStart indoors · Mar 1 – Mar 15
Broccoli, cabbageTransplant · Apr 19 – May 3
Onion setsPlant outdoors · Apr 12 – Apr 26
PotatoesPlant outdoors · Apr 19 – May 3
LettuceSow outdoors · Apr 12 – Apr 26
Carrots, beetsSow outdoors · Apr 19 – May 3
TomatoesStart indoors · Mar 15 – Mar 29
TomatoesTransplant · May 17 – May 31
Peppers, eggplantStart indoors · Mar 1 – Mar 15
Peppers, eggplantTransplant · May 24 – Jun 7
BeansSow outdoors · May 17 – May 31
Sweet cornSow outdoors · May 17 – May 31
Cucumbers, squashSow outdoors · May 17 – May 31
Fall lettuce, spinachSow outdoors · Aug 4 – Aug 18
GarlicPlant cloves · Sep 15 – Oct 20
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 10) and first fall frost (Sep 29) 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 59076 came on Mar 23 — 13 days earlier than the 1991–2020 average (Apr 5).

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 Sanders, MT.

Soil in Sanders, MT

The soil mapped at the center of ZIP 59076 is Lismas — clay, well drained.

TextureClayholds water and nutrients; slow to drain and warm up
pH7.5slightly alkaline; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter0.75%low — add compost
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Lismas clay.

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 59076; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Sanders, MT

Summer high88 °Faverage high, July
Winter low12 °Faverage low, January
Hot days31days a year at 90 °F or more
Freezing nights161nights a year at 32 °F or less
Growing degree days2,490base 50 °F — the season’s usable heat
Longest day15 h 48 mindaylight on June 21
Shortest day8 h 36 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation14.9 inper year, rain and melted snow
Snowfall37 inper year

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 35 °F, low 12 °F 35°12° JanFebruary: average high 39 °F, low 15 °F 39°15° FebMarch: average high 51 °F, low 24 °F 51°24° MarApril: average high 61 °F, low 33 °F 61°33° AprMay: average high 70 °F, low 43 °F 70°43° MayJune: average high 79 °F, low 52 °F 79°52° JunJuly: average high 88 °F, low 58 °F 88°58° JulAugust: average high 86 °F, low 55 °F 86°55° AugSeptember: average high 75 °F, low 46 °F 75°46° SepOctober: average high 60 °F, low 34 °F 60°34° OctNovember: average high 47 °F, low 23 °F 47°23° NovDecember: average high 36 °F, low 15 °F 36°15° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″January: 0.61 in precipitation, 8.3 in snowfall 0.6❄8 JanFebruary: 0.58 in precipitation, 5.4 in snowfall 0.6❄5 FebMarch: 0.80 in precipitation, 5.6 in snowfall 0.8❄6 MarApril: 1.72 in precipitation, 2.5 in snowfall 1.7❄3 AprMay: 2.47 in precipitation, 0.8 in snowfall 2.5❄1 MayJune: 2.22 in precipitation 2.2 JunJuly: 1.51 in precipitation 1.5 JulAugust: 1.16 in precipitation 1.2 AugSeptember: 1.40 in precipitation, 0.1 in snowfall 1.4 SepOctober: 1.38 in precipitation, 2.7 in snowfall 1.4❄3 OctNovember: 0.59 in precipitation, 4.2 in snowfall 0.6❄4 NovDecember: 0.48 in precipitation, 7.5 in snowfall 0.5❄8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Hysham, MT (7 mi away); precipitation: Hysham, MT (7 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

590384b
Hysham, MT · 8 mi
593274b
Forsyth, MT · 19 mi
590104b
Bighorn, MT · 25 mi
590394b
Ingomar, MT · 30 mi
593235a
Colstrip, MT · 30 mi
590834b
Sumatra, MT · 30 mi
593474b
Rosebud, MT · 35 mi
590244b
Custer, MT · 35 mi

Montana planting zones →

Questions about 59076

What planting zone is ZIP code 59076?

ZIP code 59076 (Sanders, 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 Sanders, MT?

The median last spring frost (32 °F) near 59076 is May 10; after May 22 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Hysham station.

When is the first frost in Sanders, MT?

The median first fall frost near 59076 is September 29, giving a median frost-free growing season of 141 days.

When should I plant tomatoes in 59076?

Start tomato seeds indoors around Mar 15 – Mar 29 and set transplants outside around May 17 – May 31, one to three weeks after the median last frost.

How much rain and snow does 59076 get?

About 14.9 inches of precipitation a year and 37 inches of snowfall (NOAA 1991–2020 normals, Hysham station).

How hot do summers get in Sanders, MT?

The average high peaks at 88 °F in July, with about 31 days a year at 90 °F or more.

What kind of soil does 59076 have?

The USDA soil survey maps Lismas at the center of ZIP 59076: clay, well drained, pH about 7.5 (slightly alkaline).

Did spring come early in Sanders, MT in 2026?

Spring leaf-out near 59076 came on Mar 23 in 2026, 13 days earlier than the 1991–2020 average (Apr 5), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Sanders, MT?

Long-day onions: the longest day near 59076 is 15 h 48 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 59076 change?

Yes. The 2012 USDA map put 59076 in zone 4a; the 2023 map puts it in zone 4b. The newer map uses 1991–2020 data and more weather stations.