Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 59926 — Martin City, MT

ZIP code 59926 (Martin City, Flathead County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is May 9 and the first fall frost October 1.

Where ZIP 59926 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.

Zone5b−15 to −10 °F

Coldest night−26.1 to −23.3 °C

Last frostMay 9

First frostOct 1

2012 zone5a

Was 5a 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 5b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Martin City, 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 Martin City, MT

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostMay 9median — 50% chance of a later frost

Safe for tender plantsMay 30only 10% chance of frost after

First fall frostOctober 1median — 10% chance by Sep 13

Growing season141 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 27 and returns around October 14.

From the NOAA station Hungry Horse Dam, MT — within 1 mile, elevation 3,160 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 59926

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 28 – Apr 11

SpinachSow outdoors · Mar 28 – Apr 18

Broccoli, cabbageStart indoors · Feb 28 – Mar 14

Broccoli, cabbageTransplant · Apr 18 – May 2

Onion setsPlant outdoors · Apr 11 – Apr 25

PotatoesPlant outdoors · Apr 18 – May 2

LettuceSow outdoors · Apr 11 – Apr 25

Carrots, beetsSow outdoors · Apr 18 – May 2

TomatoesStart indoors · Mar 14 – Mar 28

TomatoesTransplant · May 16 – May 30

Peppers, eggplantStart indoors · Feb 28 – Mar 14

Peppers, eggplantTransplant · May 23 – Jun 6

BeansSow outdoors · May 16 – May 30

Sweet cornSow outdoors · May 16 – May 30

Cucumbers, squashSow outdoors · May 16 – May 30

Fall lettuce, spinachSow outdoors · Aug 6 – Aug 20

GarlicPlant cloves · Sep 17 – Oct 22

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 9) and first fall frost (Oct 1) 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 59926 came on Apr 24 — 5 days earlier than the 1991–2020 average (Apr 29).

average
Apr 292026
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 5b in Montana

561 plants native to the lower 48 states, recorded in Montana, and rated by the USDA to survive −15 °F or colder — the bottom of zone 5b. Each links to its USDA PLANTS profile.

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 Martin City, MT.

Soil in Martin City, MT

The soil mapped at the center of ZIP 59926 is Dystric Cryochrepts — moderately decomposed plant material.

TextureModerately decomposed plant materialtop layer

pH6.5neutral; most vegetables like 6.0–7.0

Organic matter33%high

Hydrologic groupCwater soaks in slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Dystric Cryochrepts, till substratum-Dystric Cryochrepts, residuum substratum complex, hilly.

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 59926; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Martin City, MT

Summer high82 °Faverage high, July

Winter low20 °Faverage low, January

Hot days16days a year at 90 °F or more

Freezing nights169nights a year at 32 °F or less

Growing degree days1,735base 50 °F — the season’s usable heat

Longest day16 h 06 mindaylight on June 21

Shortest day8 h 19 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation34.6 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Hungry Horse Dam, MT (within 1 mile); precipitation: Hungry Horse Dam, MT (within 1 mile). 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.

599195b

Hungry Horse, MT · 3 mi

599215a

Lake Mc Donald, MT · 4 mi

599135a

Coram, MT · 6 mi

599125a

Columbia Falls, MT · 10 mi

599045b

Kalispell, MT · 14 mi

599165a

Essex, MT · 16 mi

599015b

Kalispell, MT · 21 mi

599035b

Kalispell, MT · 22 mi

Montana planting zones →

Questions about 59926

What planting zone is ZIP code 59926?

ZIP code 59926 (Martin City, MT) is in USDA hardiness zone 5b on the 2023 map: the coldest night of an average winter reaches −15 to −10 °F (−26.1 to −23.3 °C).

When is the last frost in Martin City, MT?

The median last spring frost (32 °F) near 59926 is May 9; after May 30 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Hungry Horse Dam station.

When is the first frost in Martin City, MT?

The median first fall frost near 59926 is October 1, giving a median frost-free growing season of 141 days.

When should I plant tomatoes in 59926?

Start tomato seeds indoors around Mar 14 – Mar 28 and set transplants outside around May 16 – May 30, one to three weeks after the median last frost.

How much rain and snow does 59926 get?

About 34.6 inches of precipitation a year (NOAA 1991–2020 normals, Hungry Horse Dam station).

How hot do summers get in Martin City, MT?

The average high peaks at 82 °F in July, with about 16 days a year at 90 °F or more.

What kind of soil does 59926 have?

The USDA soil survey maps Dystric Cryochrepts at the center of ZIP 59926: moderately decomposed plant material, pH about 6.5 (neutral).

Did spring come early in Martin City, MT in 2026?

Spring leaf-out near 59926 came on Apr 24 in 2026, 5 days earlier than the 1991–2020 average (Apr 29), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Martin City, MT?

Long-day onions: the longest day near 59926 is 16 h 06 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 59926 change?

Yes. The 2012 USDA map put 59926 in zone 5a; the 2023 map puts it in zone 5b. The newer map uses 1991–2020 data and more weather stations.