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

Planting zone for 55722 — Coleraine, MN

ZIP code 55722 (Coleraine, Itasca County) is in USDA zone 4a: the coldest winter night averages −30 to −25 °F. The median last spring frost is May 17 and the first fall frost September 24.

Where ZIP 55722 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 17
First frostSep 24
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 Coleraine, MN…

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 Coleraine, MN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 17median — 50% chance of a later frost
Safe for tender plantsMay 31only 10% chance of frost after
First fall frostSeptember 24median — 10% chance by Sep 10
Growing season130 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 6 and returns around October 5.

From the NOAA station Grand Rpds Forest Lab, MN — 4 miles away, elevation 1,309 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 55722

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 5 – Apr 19
SpinachSow outdoors · Apr 5 – Apr 26
Broccoli, cabbageStart indoors · Mar 8 – Mar 22
Broccoli, cabbageTransplant · Apr 26 – May 10
Onion setsPlant outdoors · Apr 19 – May 3
PotatoesPlant outdoors · Apr 26 – May 10
LettuceSow outdoors · Apr 19 – May 3
Carrots, beetsSow outdoors · Apr 26 – May 10
TomatoesStart indoors · Mar 22 – Apr 5
TomatoesTransplant · May 24 – Jun 7
Peppers, eggplantStart indoors · Mar 8 – Mar 22
Peppers, eggplantTransplant · May 31 – Jun 14
BeansSow outdoors · May 24 – Jun 7
Sweet cornSow outdoors · May 24 – Jun 7
Cucumbers, squashSow outdoors · May 24 – Jun 7
Fall lettuce, spinachSow outdoors · Jul 30 – Aug 13
GarlicPlant cloves · Sep 10 – Oct 15
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 17) and first fall frost (Sep 24) 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 55722 came on Apr 23 — 3 days earlier than the 1991–2020 average (Apr 26).

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 Minnesota

445 plants native to the lower 48 states, recorded in Minnesota, and rated by the USDA to survive −30 °F or colder — the bottom of zone 4a. Each links to its USDA PLANTS profile.

Trees 45

Shrubs 77

Wildflowers & perennials 173

Grasses 140

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 Coleraine, MN.

Soil in Coleraine, MN

The soil mapped at the center of ZIP 55722 is Warba — moderately decomposed plant material, well drained.

TextureModerately decomposed plant materialtop layer
DrainageWell drainednatural drainage class
Organic matter60%high
Hydrologic groupCwater soaks in slowly
Farmland classprime farmlandUSDA classification

Map unit: Warba very fine sandy loam, 1 to 8 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 55722; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Coleraine, MN

Summer high80 °Faverage high, July
Winter low−1 °Faverage low, January
Hot days6days a year at 90 °F or more
Freezing nights187nights a year at 32 °F or less
Growing degree days1,866base 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)
Precipitation29.4 inper year, rain and melted snow
Snowfall60 inper year; 129 days with snow on the ground

Average high and low, by month

−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 19 °F, low -1 °F 19°−1° JanFebruary: average high 26 °F, low 2 °F 26°2° FebMarch: average high 39 °F, low 15 °F 39°15° MarApril: average high 53 °F, low 28 °F 53°28° AprMay: average high 66 °F, low 40 °F 66°40° MayJune: average high 75 °F, low 51 °F 75°51° JunJuly: average high 80 °F, low 55 °F 80°55° JulAugust: average high 78 °F, low 53 °F 78°53° AugSeptember: average high 68 °F, low 45 °F 68°45° SepOctober: average high 53 °F, low 33 °F 53°33° OctNovember: average high 36 °F, low 20 °F 36°20° NovDecember: average high 23 °F, low 7 °F 23°7° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 0.97 in precipitation, 12.2 in snowfall 1.0❄12 JanFebruary: 0.85 in precipitation, 9.7 in snowfall 0.8❄10 FebMarch: 1.33 in precipitation, 7.5 in snowfall 1.3❄8 MarApril: 2.10 in precipitation, 5.6 in snowfall 2.1❄6 AprMay: 3.23 in precipitation, 0.2 in snowfall 3.2 MayJune: 4.70 in precipitation 4.7 JunJuly: 4.14 in precipitation 4.1 JulAugust: 3.40 in precipitation 3.4 AugSeptember: 3.05 in precipitation 3.0 SepOctober: 2.79 in precipitation, 2 in snowfall 2.8❄2 OctNovember: 1.59 in precipitation, 9 in snowfall 1.6❄9 NovDecember: 1.23 in precipitation, 13.4 in snowfall 1.2❄13 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Grand Rpds Forest Lab, MN (4 mi away); precipitation: Grand Rpds Forest Lab, MN (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.

Minnesota planting zones →

Questions about 55722

What planting zone is ZIP code 55722?

ZIP code 55722 (Coleraine, MN) 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 Coleraine, MN?

The median last spring frost (32 °F) near 55722 is May 17; after May 31 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Grand Rpds Forest Lab station.

When is the first frost in Coleraine, MN?

The median first fall frost near 55722 is September 24, giving a median frost-free growing season of 130 days.

When should I plant tomatoes in 55722?

Start tomato seeds indoors around Mar 22 – Apr 5 and set transplants outside around May 24 – Jun 7, one to three weeks after the median last frost.

How much rain and snow does 55722 get?

About 29.4 inches of precipitation a year and 60 inches of snowfall (NOAA 1991–2020 normals, Grand Rpds Forest Lab station).

How hot do summers get in Coleraine, MN?

The average high peaks at 80 °F in July, with about 6 days a year at 90 °F or more.

What kind of soil does 55722 have?

The USDA soil survey maps Warba at the center of ZIP 55722: moderately decomposed plant material, well drained.

Did spring come early in Coleraine, MN in 2026?

Spring leaf-out near 55722 came on Apr 23 in 2026, 3 days earlier than the 1991–2020 average (Apr 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Coleraine, MN?

Long-day onions: the longest day near 55722 is 15 h 56 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 55722 change?

Yes. The 2012 USDA map put 55722 in zone 3b; the 2023 map puts it in zone 4a. The newer map uses 1991–2020 data and more weather stations.