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

Planting zone for 56668 — Ranier, MN

ZIP code 56668 (Ranier, Koochiching County) is in USDA zone 3a: the coldest winter night averages −40 to −35 °F. The median last spring frost is May 29 and the first fall frost September 13.

Where ZIP 56668 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.

Zone3a−40 to −35 °F

Coldest night−40 to −37.2 °C

Last frostMay 29

First frostSep 13

2012 zone3a

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 3a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Ranier, 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 Ranier, MN

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 29median — 50% chance of a later frost

Safe for tender plantsJune 16only 10% chance of frost after

First fall frostSeptember 13median — 10% chance by Aug 30

Growing season109 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 14 and returns around September 26.

From the NOAA station Intl Falls Intl Airport, MN — 4 miles away, elevation 1,184 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 56668

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 17 – May 1

SpinachSow outdoors · Apr 17 – May 8

Broccoli, cabbageStart indoors · Mar 20 – Apr 3

Broccoli, cabbageTransplant · May 8 – May 22

Onion setsPlant outdoors · May 1 – May 15

PotatoesPlant outdoors · May 8 – May 22

LettuceSow outdoors · May 1 – May 15

Carrots, beetsSow outdoors · May 8 – May 22

TomatoesStart indoors · Apr 3 – Apr 17

TomatoesTransplant · Jun 5 – Jun 19

Peppers, eggplantStart indoors · Mar 20 – Apr 3

Peppers, eggplantTransplant · Jun 12 – Jun 26

BeansSow outdoors · Jun 5 – Jun 19

Sweet cornSow outdoors · Jun 5 – Jun 19

Cucumbers, squashSow outdoors · Jun 5 – Jun 19

Fall lettuce, spinachSow outdoors · Jul 19 – Aug 2

GarlicPlant cloves · Aug 30 – Oct 4

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 29) and first fall frost (Sep 13) 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 56668 came on May 9 — 10 days later than the 1991–2020 average (Apr 29).

average
Apr 292026
May 9

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 3a in Minnesota

113 plants native to the lower 48 states, recorded in Minnesota, and rated by the USDA to survive −40 °F or colder — the bottom of zone 3a. 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 Ranier, MN.

Soil in Ranier, MN

The soil mapped at the center of ZIP 56668 is Baudette — silt loam, moderately well drained.

TextureSilt loama good balance for most vegetables

pH5.8moderately acidic; most vegetables like 6.0–7.0

DrainageModerately well drainednatural drainage class

Organic matter5%high

Hydrologic groupCwater soaks in slowly

Farmland classprime farmlandUSDA classification

Map unit: Baudette-Littleswan complex, 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 56668; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Ranier, MN

Summer high78 °Faverage high, July

Winter low−6 °Faverage low, January

Hot days2days a year at 90 °F or more

Freezing nights200nights a year at 32 °F or less

Growing degree days1,543base 50 °F — the season’s usable heat

Longest day16 h 09 mindaylight on June 21

Shortest day8 h 17 mindaylight on December 21

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

Precipitation25.4 inper year, rain and melted snow

Snowfall73 inper year; 136 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Intl Falls Intl Airport, MN (4 mi away); precipitation: Intl Falls Intl Airport, MN (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

566793b

South International Falls, MN · 3 mi

566493b

International Falls, MN · 10 mi

566693b

Kabetogama, MN · 18 mi

566533b

Littlefork, MN · 25 mi

566543a

Loman, MN · 31 mi

557723b

Nett Lake, MN · 37 mi

566293b

Birchdale, MN · 38 mi

557713b

Orr, MN · 40 mi

Minnesota planting zones →

Questions about 56668

What planting zone is ZIP code 56668?

ZIP code 56668 (Ranier, MN) is in USDA hardiness zone 3a on the 2023 map: the coldest night of an average winter reaches −40 to −35 °F (−40 to −37.2 °C).

When is the last frost in Ranier, MN?

The median last spring frost (32 °F) near 56668 is May 29; after June 16 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Intl Falls Intl Airport station.

When is the first frost in Ranier, MN?

The median first fall frost near 56668 is September 13, giving a median frost-free growing season of 109 days.

When should I plant tomatoes in 56668?

Start tomato seeds indoors around Apr 3 – Apr 17 and set transplants outside around Jun 5 – Jun 19, one to three weeks after the median last frost.

How much rain and snow does 56668 get?

About 25.4 inches of precipitation a year and 73 inches of snowfall (NOAA 1991–2020 normals, Intl Falls Intl Airport station).

How hot do summers get in Ranier, MN?

The average high peaks at 78 °F in July, with about 2 days a year at 90 °F or more.

What kind of soil does 56668 have?

The USDA soil survey maps Baudette at the center of ZIP 56668: silt loam, moderately well drained, pH about 5.8 (moderately acidic).

Did spring come early in Ranier, MN in 2026?

Spring leaf-out near 56668 came on May 9 in 2026, 10 days later than the 1991–2020 average (Apr 29), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Ranier, MN?

Long-day onions: the longest day near 56668 is 16 h 09 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).