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

Planting zone for 59226 — Froid, MT

ZIP code 59226 (Froid, Roosevelt County) is in USDA zone 4a: the coldest winter night averages −30 to −25 °F. The median last spring frost is May 16 and the first fall frost September 18.

Where ZIP 59226 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.

Zone4a−30 to −25 °F

Coldest night−34.4 to −31.7 °C

Last frostMay 16

First frostSep 18

2012 zone3b

Was 3b 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 4a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Froid, 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 Froid, MT

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 16median — 50% chance of a later frost

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

First fall frostSeptember 18median — 10% chance by Sep 7

Growing season125 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 5 and returns around September 25.

From the NOAA station Medicine Lake 3 Se, MT — 10 miles away, elevation 1,942 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 59226

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 4 – Apr 18

SpinachSow outdoors · Apr 4 – Apr 25

Broccoli, cabbageStart indoors · Mar 7 – Mar 21

Broccoli, cabbageTransplant · Apr 25 – May 9

Onion setsPlant outdoors · Apr 18 – May 2

PotatoesPlant outdoors · Apr 25 – May 9

LettuceSow outdoors · Apr 18 – May 2

Carrots, beetsSow outdoors · Apr 25 – May 9

TomatoesStart indoors · Mar 21 – Apr 4

TomatoesTransplant · May 23 – Jun 6

Peppers, eggplantStart indoors · Mar 7 – Mar 21

Peppers, eggplantTransplant · May 30 – Jun 13

BeansSow outdoors · May 23 – Jun 6

Sweet cornSow outdoors · May 23 – Jun 6

Cucumbers, squashSow outdoors · May 23 – Jun 6

Fall lettuce, spinachSow outdoors · Jul 24 – Aug 7

GarlicPlant cloves · Sep 4 – Oct 9

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 16) and first fall frost (Sep 18) 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 59226 came on Apr 20 — about the same time as the 1991–2020 average (Apr 18).

average
Apr 182026
Apr 20

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 4a in Montana

439 plants native to the lower 48 states, recorded in Montana, and rated by the USDA to survive −30 °F or colder — the bottom of zone 4a. 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 Froid, MT.

Soil in Froid, MT

The soil mapped at the center of ZIP 59226 is Parshall — sandy loam, well drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding

pH7.0neutral; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter2.5%moderate

Hydrologic groupAwater soaks in fast

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Parshall sandy loam, 0 to 4 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 59226; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Froid, MT

Summer high83 °Faverage high, July

Winter low0 °Faverage low, January

Hot days18days a year at 90 °F or more

Freezing nights192nights a year at 32 °F or less

Growing degree days2,037base 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)

Precipitation15.2 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: Medicine Lake 3 Se, MT (10 mi away); precipitation: Homestead 5 E, MT (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

592423b

Homestead, MT · 6 mi

592473b

Medicine Lake, MT · 12 mi

592583b

Reserve, MT · 17 mi

592184a

Culbertson, MT · 19 mi

592134a

Brockton, MT · 20 mi

592124a

Bainville, MT · 20 mi

Montana planting zones →

Questions about 59226

What planting zone is ZIP code 59226?

ZIP code 59226 (Froid, MT) is in USDA hardiness zone 4a on the 2023 map: the coldest night of an average winter reaches −30 to −25 °F (−34.4 to −31.7 °C).

When is the last frost in Froid, MT?

The median last spring frost (32 °F) near 59226 is May 16; after May 30 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Medicine Lake 3 Se station.

When is the first frost in Froid, MT?

The median first fall frost near 59226 is September 18, giving a median frost-free growing season of 125 days.

When should I plant tomatoes in 59226?

Start tomato seeds indoors around Mar 21 – Apr 4 and set transplants outside around May 23 – Jun 6, one to three weeks after the median last frost.

How much rain and snow does 59226 get?

About 15.2 inches of precipitation a year (NOAA 1991–2020 normals, Homestead 5 E station).

How hot do summers get in Froid, MT?

The average high peaks at 83 °F in July, with about 18 days a year at 90 °F or more.

What kind of soil does 59226 have?

The USDA soil survey maps Parshall at the center of ZIP 59226: sandy loam, well drained, pH about 7.0 (neutral).

Did spring come early in Froid, MT in 2026?

Spring leaf-out near 59226 came on Apr 20 in 2026, about the same as the 1991–2020 average (Apr 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Froid, MT?

Long-day onions: the longest day near 59226 is 16 h 06 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 59226 change?

Yes. The 2012 USDA map put 59226 in zone 3b; the 2023 map puts it in zone 4a. The newer map uses 1991–2020 data and more weather stations.