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

Planting zone for 59867 — Saltese, MT

ZIP code 59867 (Saltese, Mineral County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is June 10 and the first fall frost September 23.

Where ZIP 59867 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.

Zone6a−10 to −5 °F
Coldest night−23.3 to −20.6 °C
Last frostJun 10
First frostSep 23
2012 zone5b

Was 5b 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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Saltese, 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 Saltese, MT

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostJune 10median — 50% chance of a later frost
Safe for tender plantsJune 25only 10% chance of frost after
First fall frostSeptember 23median — 10% chance by Sep 4
Growing season104 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 21 and returns around October 5.

From the NOAA station Mullan Pass Vor/Dme, ID — 6 miles away, elevation 6,027 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 59867

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 29 – May 13
SpinachSow outdoors · Apr 29 – May 20
Broccoli, cabbageStart indoors · Apr 1 – Apr 15
Broccoli, cabbageTransplant · May 20 – Jun 3
Onion setsPlant outdoors · May 13 – May 27
PotatoesPlant outdoors · May 20 – Jun 3
LettuceSow outdoors · May 13 – May 27
Carrots, beetsSow outdoors · May 20 – Jun 3
TomatoesStart indoors · Apr 15 – Apr 29
TomatoesTransplant · Jun 17 – Jul 1
Peppers, eggplantStart indoors · Apr 1 – Apr 15
Peppers, eggplantTransplant · Jun 24 – Jul 8
BeansSow outdoors · Jun 17 – Jul 1
Sweet cornSow outdoors · Jun 17 – Jul 1
Cucumbers, squashSow outdoors · Jun 17 – Jul 1
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 (Jun 10) 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 59867 came on Apr 26 — 14 days earlier than the 1991–2020 average (May 10).

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 6a in Montana

572 plants native to the lower 48 states, recorded in Montana, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 28

Shrubs 100

Wildflowers & perennials 266

Grasses 164

Vines 3

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 Saltese, MT.

Soil in Saltese, MT

The soil mapped at the center of ZIP 59867 is Mitten — moderately decomposed plant material, well drained.

TextureModerately decomposed plant materialtop layer
pH5.0strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter70%high
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Mitten-Holloway families, association, high stream terraces and escarpments.

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 59867; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Saltese, MT

Summer high70 °Faverage high, July
Winter low18 °Faverage low, December
Hot days0days a year at 90 °F or more
Freezing nights206nights a year at 32 °F or less
Growing degree days999base 50 °F — the season’s usable heat
Longest day15 h 57 mindaylight on June 21
Shortest day8 h 27 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation45.1 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°32 °FJanuary: average high 28 °F, low 19 °F 28°19° JanFebruary: average high 28 °F, low 19 °F 28°19° FebMarch: average high 34 °F, low 22 °F 34°22° MarApril: average high 40 °F, low 27 °F 40°27° AprMay: average high 50 °F, low 36 °F 50°36° MayJune: average high 58 °F, low 42 °F 58°42° JunJuly: average high 70 °F, low 52 °F 70°52° JulAugust: average high 69 °F, low 51 °F 69°51° AugSeptember: average high 59 °F, low 44 °F 59°44° SepOctober: average high 44 °F, low 32 °F 44°32° OctNovember: average high 32 °F, low 24 °F 32°24° NovDecember: average high 27 °F, low 18 °F 27°18° Dec

Precipitation by month inches

0″2″4″6″January: 5.90 in precipitation 5.9 JanFebruary: 4.66 in precipitation 4.7 FebMarch: 5.03 in precipitation 5.0 MarApril: 3.60 in precipitation 3.6 AprMay: 2.96 in precipitation 3.0 MayJune: 3.12 in precipitation 3.1 JunJuly: 1.09 in precipitation 1.1 JulAugust: 1.14 in precipitation 1.1 AugSeptember: 1.65 in precipitation 1.6 SepOctober: 3.89 in precipitation 3.9 OctNovember: 6.01 in precipitation 6.0 NovDecember: 6.04 in precipitation 6.0 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Mullan Pass Vor/Dme, ID (6 mi away); precipitation: Mullan Pass Vor/Dme, ID (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

Montana planting zones →

Questions about 59867

What planting zone is ZIP code 59867?

ZIP code 59867 (Saltese, MT) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).

When is the last frost in Saltese, MT?

The median last spring frost (32 °F) near 59867 is June 10; after June 25 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Mullan Pass Vor/Dme station.

When is the first frost in Saltese, MT?

The median first fall frost near 59867 is September 23, giving a median frost-free growing season of 104 days.

When should I plant tomatoes in 59867?

Start tomato seeds indoors around Apr 15 – Apr 29 and set transplants outside around Jun 17 – Jul 1, one to three weeks after the median last frost.

How much rain and snow does 59867 get?

About 45.1 inches of precipitation a year (NOAA 1991–2020 normals, Mullan Pass Vor/Dme station).

How hot do summers get in Saltese, MT?

The average high peaks at 70 °F in July, with about 0 days a year at 90 °F or more.

What kind of soil does 59867 have?

The USDA soil survey maps Mitten at the center of ZIP 59867: moderately decomposed plant material, well drained, pH about 5.0 (strongly acidic).

Did spring come early in Saltese, MT in 2026?

Spring leaf-out near 59867 came on Apr 26 in 2026, 14 days earlier than the 1991–2020 average (May 10), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Saltese, MT?

Long-day onions: the longest day near 59867 is 15 h 57 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 59867 change?

Yes. The 2012 USDA map put 59867 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.