Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 30, 2026

Planting zone for 59854 — Ovando, MT

ZIP code 59854 (Ovando, Powell County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is May 20 and the first fall frost September 22.

Where ZIP 59854 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 frostMay 20

First frostSep 22

2012 zone4a

Was 4a on the 2012 map — a full 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 Ovando, 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 Ovando, MT

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 20median — 50% chance of a later frost

Safe for tender plantsJune 7only 10% chance of frost after

First fall frostSeptember 22median — 10% chance by Sep 5

Growing season120 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 3 and returns around October 4.

From the NOAA station Lindbergh Lake, MT — 24 miles away, elevation 4,321 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 59854

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 8 – Apr 22

SpinachSow outdoors · Apr 8 – Apr 29

Broccoli, cabbageStart indoors · Mar 11 – Mar 25

Broccoli, cabbageTransplant · Apr 29 – May 13

Onion setsPlant outdoors · Apr 22 – May 6

PotatoesPlant outdoors · Apr 29 – May 13

LettuceSow outdoors · Apr 22 – May 6

Carrots, beetsSow outdoors · Apr 29 – May 13

TomatoesStart indoors · Mar 25 – Apr 8

TomatoesTransplant · May 27 – Jun 10

Peppers, eggplantStart indoors · Mar 11 – Mar 25

Peppers, eggplantTransplant · Jun 3 – Jun 17

BeansSow outdoors · May 27 – Jun 10

Sweet cornSow outdoors · May 27 – Jun 10

Cucumbers, squashSow outdoors · May 27 – Jun 10

Fall lettuce, spinachSow outdoors · Jul 28 – Aug 11

GarlicPlant cloves · Sep 8 – Oct 13

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 20) and first fall frost (Sep 22) 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 59854 came on May 10 — 6 days earlier than the 1991–2020 average (May 16).

average
May 162026
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 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 Ovando, MT.

Soil in Ovando, MT

The soil mapped at the center of ZIP 59854 is McCay — 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: McCay, Vaywood and Muddycreek families, cirque basins.

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 59854; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Ovando, MT

Summer high83 °Faverage high, July

Winter low12 °Faverage low, January

Hot days15days a year at 90 °F or more

Freezing nights215nights a year at 32 °F or less

Growing degree days1,308base 50 °F — the season’s usable heat

Longest day15 h 56 mindaylight on June 21

Shortest day8 h 28 mindaylight on December 21

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

Precipitation21.8 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: Seeley Lake Rs, MT (14 mi away); precipitation: Seeley Lake 0.3 Ese, MT (13 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.

598685a

Seeley Lake, MT · 15 mi

Helmville, MT · 31 mi

594104b

Augusta, MT · 32 mi

598656a

Saint Ignatius, MT · 36 mi

598325b

Drummond, MT · 41 mi

Montana planting zones →

Questions about 59854

What planting zone is ZIP code 59854?

ZIP code 59854 (Ovando, 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 Ovando, MT?

The median last spring frost (32 °F) near 59854 is May 20; after June 7 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Lindbergh Lake station.

When is the first frost in Ovando, MT?

The median first fall frost near 59854 is September 22, giving a median frost-free growing season of 120 days.

When should I plant tomatoes in 59854?

Start tomato seeds indoors around Mar 25 – Apr 8 and set transplants outside around May 27 – Jun 10, one to three weeks after the median last frost.

How much rain and snow does 59854 get?

About 21.8 inches of precipitation a year (NOAA 1991–2020 normals, Seeley Lake 0.3 Ese station).

How hot do summers get in Ovando, MT?

The average high peaks at 83 °F in July, with about 15 days a year at 90 °F or more.

What kind of soil does 59854 have?

The USDA soil survey maps McCay at the center of ZIP 59854: moderately decomposed plant material, well drained, pH about 5.0 (strongly acidic).

Did spring come early in Ovando, MT in 2026?

Spring leaf-out near 59854 came on May 10 in 2026, 6 days earlier than the 1991–2020 average (May 16), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Ovando, MT?

Long-day onions: the longest day near 59854 is 15 h 56 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 59854 change?

Yes. The 2012 USDA map put 59854 in zone 4a; the 2023 map puts it in zone 5a. The newer map uses 1991–2020 data and more weather stations.