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

Planting zone for 55769 — Nashwauk, MN

ZIP code 55769 (Nashwauk, Itasca County) is in USDA zone 3b: the coldest winter night averages −35 to −30 °F. The median last spring frost is June 5 and the first fall frost September 8.

Where ZIP 55769 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 frostJun 5
First frostSep 8
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 Nashwauk, 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 Nashwauk, MN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostJune 5median — 50% chance of a later frost
Safe for tender plantsJune 25only 10% chance of frost after
First fall frostSeptember 8median — 10% chance by Aug 23
Growing season93 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 23 and returns around September 21.

From the NOAA station Hibbing Chisholm Hibbing Airport, MN — 17 miles away, elevation 1,352 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 55769

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 24 – May 8
SpinachSow outdoors · Apr 24 – May 15
Broccoli, cabbageStart indoors · Mar 27 – Apr 10
Broccoli, cabbageTransplant · May 15 – May 29
Onion setsPlant outdoors · May 8 – May 22
PotatoesPlant outdoors · May 15 – May 29
LettuceSow outdoors · May 8 – May 22
Carrots, beetsSow outdoors · May 15 – May 29
TomatoesStart indoors · Apr 10 – Apr 24
TomatoesTransplant · Jun 12 – Jun 26
Peppers, eggplantStart indoors · Mar 27 – Apr 10
Peppers, eggplantTransplant · Jun 19 – Jul 3
BeansSow outdoors · Jun 12 – Jun 26
Sweet cornSow outdoors · Jun 12 – Jun 26
Cucumbers, squashSow outdoors · Jun 12 – Jun 26
Fall lettuce, spinachSow outdoors · Jul 14 – Jul 28
GarlicPlant cloves · Aug 25 – Sep 29
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jun 5) and first fall frost (Sep 8) 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 55769 came on Apr 29 — 3 days later 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).

Soil in Nashwauk, MN

The soil mapped at the center of ZIP 55769 is Nashwauk — fine sandy loam, moderately well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding
pH5.8moderately acidic; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter4%moderate
Hydrologic groupDwater soaks in very slowly
Farmland classprime farmlandUSDA classification

Map unit: Nashwauk fine sandy loam, 1 to 10 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 55769; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Nashwauk, MN

Summer high77 °Faverage high, July
Winter low−4 °Faverage low, January
Hot days2days a year at 90 °F or more
Freezing nights205nights a year at 32 °F or less
Growing degree days1,336base 50 °F — the season’s usable heat
Longest day15 h 58 mindaylight on June 21
Shortest day8 h 26 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation28.5 inper year, rain and melted snow

Average high and low, by month

−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 17 °F, low -4 °F 17°−4° JanFebruary: average high 23 °F, low -1 °F 23°−1° FebMarch: average high 35 °F, low 12 °F 35°12° MarApril: average high 50 °F, low 25 °F 50°25° AprMay: average high 63 °F, low 36 °F 63°36° MayJune: average high 72 °F, low 46 °F 72°46° JunJuly: average high 77 °F, low 50 °F 77°50° JulAugust: average high 75 °F, low 48 °F 75°48° AugSeptember: average high 66 °F, low 40 °F 66°40° SepOctober: average high 51 °F, low 30 °F 51°30° OctNovember: average high 34 °F, low 17 °F 34°17° NovDecember: average high 21 °F, low 3 °F 21°3° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 0.97 in precipitation 1.0 JanFebruary: 0.83 in precipitation 0.8 FebMarch: 1.21 in precipitation 1.2 MarApril: 2.02 in precipitation 2.0 AprMay: 3.03 in precipitation 3.0 MayJune: 4.28 in precipitation 4.3 JunJuly: 3.92 in precipitation 3.9 JulAugust: 3.48 in precipitation 3.5 AugSeptember: 3.26 in precipitation 3.3 SepOctober: 2.72 in precipitation 2.7 OctNovember: 1.59 in precipitation 1.6 NovDecember: 1.23 in precipitation 1.2 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Hibbing Chisholm Hibbing Airport, MN (17 mi away); precipitation: Chisholm 0.4 Wsw, MN (14 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.

Minnesota planting zones →

Questions about 55769

What planting zone is ZIP code 55769?

ZIP code 55769 (Nashwauk, 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 Nashwauk, MN?

The median last spring frost (32 °F) near 55769 is June 5; after June 25 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Hibbing Chisholm Hibbing Airport station.

When is the first frost in Nashwauk, MN?

The median first fall frost near 55769 is September 8, giving a median frost-free growing season of 93 days.

When should I plant tomatoes in 55769?

Start tomato seeds indoors around Apr 10 – Apr 24 and set transplants outside around Jun 12 – Jun 26, one to three weeks after the median last frost.

How much rain and snow does 55769 get?

About 28.5 inches of precipitation a year (NOAA 1991–2020 normals, Chisholm 0.4 Wsw station).

How hot do summers get in Nashwauk, MN?

The average high peaks at 77 °F in July, with about 2 days a year at 90 °F or more.

What kind of soil does 55769 have?

The USDA soil survey maps Nashwauk at the center of ZIP 55769: fine sandy loam, moderately well drained, pH about 5.8 (moderately acidic).

Did spring come early in Nashwauk, MN in 2026?

Spring leaf-out near 55769 came on Apr 29 in 2026, 3 days later than the 1991–2020 average (Apr 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Nashwauk, MN?

Long-day onions: the longest day near 55769 is 15 h 58 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).