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

Planting zone for 59052 — Mc Leod, MT

ZIP code 59052 (Mc Leod, Sweet Grass County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is June 1 and the first fall frost September 11.

Where ZIP 59052 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 frostJun 1

First frostSep 11

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 Mc Leod, 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 Mc Leod, MT

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostJune 1median — 50% chance of a later frost

Safe for tender plantsJune 21only 10% chance of frost after

First fall frostSeptember 11median — 10% chance by Aug 25

Growing season100 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 15 and returns around September 25.

From the NOAA station Nye #2, MT — 17 miles away, elevation 4,839 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 59052

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 20 – May 4

SpinachSow outdoors · Apr 20 – May 11

Broccoli, cabbageStart indoors · Mar 23 – Apr 6

Broccoli, cabbageTransplant · May 11 – May 25

Onion setsPlant outdoors · May 4 – May 18

PotatoesPlant outdoors · May 11 – May 25

LettuceSow outdoors · May 4 – May 18

Carrots, beetsSow outdoors · May 11 – May 25

TomatoesStart indoors · Apr 6 – Apr 20

TomatoesTransplant · Jun 8 – Jun 22

Peppers, eggplantStart indoors · Mar 23 – Apr 6

Peppers, eggplantTransplant · Jun 15 – Jun 29

BeansSow outdoors · Jun 8 – Jun 22

Sweet cornSow outdoors · Jun 8 – Jun 22

Cucumbers, squashSow outdoors · Jun 8 – Jun 22

Fall lettuce, spinachSow outdoors · Jul 17 – Jul 31

GarlicPlant cloves · Aug 28 – Oct 2

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jun 1) and first fall frost (Sep 11) 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 59052 came on May 23 — 6 days earlier than the 1991–2020 average (May 29).

average
May 292026
May 23

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.

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 Mc Leod, MT.

Soil in Mc Leod, MT

The soil mapped at the center of ZIP 59052 is Dystric Cryochrepts — very gravelly loam, well drained.

TextureVery gravelly loama good balance for most vegetables

pH5.5moderately acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter3%moderate

Hydrologic groupAwater soaks in fast

Farmland classNot prime farmlandUSDA classification

Map unit: Dystric Cryochrepts, glaciated mountain ridges.

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 59052; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mc Leod, MT

Summer high83 °Faverage high, July

Winter low19 °Faverage low, January

Hot days18days a year at 90 °F or more

Freezing nights161nights a year at 32 °F or less

Growing degree days1,652base 50 °F — the season’s usable heat

Longest day15 h 41 mindaylight on June 21

Shortest day8 h 42 mindaylight on December 21

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

Precipitation28.1 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: Nye #2, MT (17 mi away); precipitation: East Boulder Mine, MT (4 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.

590615a

Nye, MT · 14 mi

590475a

Livingston, MT · 21 mi

590285a

Fishtail, MT · 24 mi

590204b

Cooke City, MT · 25 mi

590335a

Greycliff, MT · 27 mi

590825a

Springdale, MT · 27 mi

Montana planting zones →

Questions about 59052

What planting zone is ZIP code 59052?

ZIP code 59052 (Mc Leod, 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 Mc Leod, MT?

The median last spring frost (32 °F) near 59052 is June 1; after June 21 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Nye #2 station.

When is the first frost in Mc Leod, MT?

The median first fall frost near 59052 is September 11, giving a median frost-free growing season of 100 days.

When should I plant tomatoes in 59052?

Start tomato seeds indoors around Apr 6 – Apr 20 and set transplants outside around Jun 8 – Jun 22, one to three weeks after the median last frost.

How much rain and snow does 59052 get?

About 28.1 inches of precipitation a year (NOAA 1991–2020 normals, East Boulder Mine station).

How hot do summers get in Mc Leod, 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 59052 have?

The USDA soil survey maps Dystric Cryochrepts at the center of ZIP 59052: very gravelly loam, well drained, pH about 5.5 (moderately acidic).

Did spring come early in Mc Leod, MT in 2026?

Spring leaf-out near 59052 came on May 23 in 2026, 6 days earlier than the 1991–2020 average (May 29), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mc Leod, MT?

Long-day onions: the longest day near 59052 is 15 h 41 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 59052 change?

Yes. The 2012 USDA map put 59052 in zone 4b; the 2023 map puts it in zone 5a. The newer map uses 1991–2020 data and more weather stations.