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

Planting zone for 56660 — Mizpah, MN

ZIP code 56660 (Mizpah, Koochiching County) is in USDA zone 3b: the coldest winter night averages −35 to −30 °F. The median last spring frost is May 16 and the first fall frost September 26.

Where ZIP 56660 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.

Zone3b−35 to −30 °F
Coldest night−37.2 to −34.4 °C
Last frostMay 16
First frostSep 26
2012 zone3b

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 3b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Mizpah, 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 Mizpah, MN

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 26median — 10% chance by Sep 11
Growing season131 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 5 and returns around October 8.

From the NOAA station Northome 3s, MN — 11 miles away, elevation 1,414 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 56660

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 · Aug 1 – Aug 15
GarlicPlant cloves · Sep 12 – Oct 17
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 16) and first fall frost (Sep 26) 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 56660 came on May 4 — 6 days later than the 1991–2020 average (Apr 28).

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 3b in Minnesota

287 plants native to the lower 48 states, recorded in Minnesota, and rated by the USDA to survive −35 °F or colder — the bottom of zone 3b. Each links to its USDA PLANTS profile.

Trees 33

Shrubs 50

Wildflowers & perennials 102

Grasses 93

Vines 2

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 Mizpah, MN.

Soil in Mizpah, MN

The soil mapped at the center of ZIP 56660 is Beltrami — loam, somewhat poorly drained.

TextureLoama good balance for most vegetables
pH7.0neutral; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter3%moderate
Hydrologic groupC/Dslow when drained; wet otherwise
Farmland classNot prime farmlandUSDA classification

Map unit: Beltrami-Talmoon complex, 0 to 3 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 56660; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mizpah, MN

Summer high77 °Faverage high, July
Winter low−5 °Faverage low, January
Hot days1days a year at 90 °F or more
Freezing nights195nights a year at 32 °F or less
Growing degree days1,663base 50 °F — the season’s usable heat
Longest day16 h 03 mindaylight on June 21
Shortest day8 h 22 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation26.9 inper year, rain and melted snow

Average high and low, by month

−20°−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 17 °F, low -5 °F 17°−5° JanFebruary: average high 23 °F, low -2 °F 23°−2° FebMarch: average high 35 °F, low 10 °F 35°10° MarApril: average high 50 °F, low 26 °F 50°26° AprMay: average high 63 °F, low 39 °F 63°39° MayJune: average high 72 °F, low 51 °F 72°51° JunJuly: average high 77 °F, low 55 °F 77°55° JulAugust: average high 76 °F, low 52 °F 76°52° AugSeptember: average high 67 °F, low 45 °F 67°45° SepOctober: average high 52 °F, low 34 °F 52°34° OctNovember: average high 35 °F, low 19 °F 35°19° NovDecember: average high 22 °F, low 4 °F 22°4° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 0.77 in precipitation 0.8 JanFebruary: 0.64 in precipitation 0.6 FebMarch: 1.20 in precipitation 1.2 MarApril: 1.82 in precipitation 1.8 AprMay: 3.01 in precipitation 3.0 MayJune: 4.23 in precipitation 4.2 JunJuly: 3.84 in precipitation 3.8 JulAugust: 3.20 in precipitation 3.2 AugSeptember: 3.10 in precipitation 3.1 SepOctober: 2.68 in precipitation 2.7 OctNovember: 1.36 in precipitation 1.4 NovDecember: 1.03 in precipitation 1.0 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Northome 3s, MN (11 mi away); precipitation: Northome 3s, MN (11 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 3b.

Minnesota planting zones →

Questions about 56660

What planting zone is ZIP code 56660?

ZIP code 56660 (Mizpah, MN) is in USDA hardiness zone 3b on the 2023 map: the coldest night of an average winter reaches −35 to −30 °F (−37.2 to −34.4 °C).

When is the last frost in Mizpah, MN?

The median last spring frost (32 °F) near 56660 is May 16; after May 30 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Northome 3s station.

When is the first frost in Mizpah, MN?

The median first fall frost near 56660 is September 26, giving a median frost-free growing season of 131 days.

When should I plant tomatoes in 56660?

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 56660 get?

About 26.9 inches of precipitation a year (NOAA 1991–2020 normals, Northome 3s station).

How hot do summers get in Mizpah, MN?

The average high peaks at 77 °F in July, with about 1 days a year at 90 °F or more.

What kind of soil does 56660 have?

The USDA soil survey maps Beltrami at the center of ZIP 56660: loam, somewhat poorly drained, pH about 7.0 (neutral).

Did spring come early in Mizpah, MN in 2026?

Spring leaf-out near 56660 came on May 4 in 2026, 6 days later than the 1991–2020 average (Apr 28), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mizpah, MN?

Long-day onions: the longest day near 56660 is 16 h 03 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).