Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 55733 — Esko, MN

ZIP code 55733 (Esko, Carlton County) is in USDA zone 4b: the coldest winter night averages −25 to −20 °F. The median last spring frost is May 26 and the first fall frost September 23.

Where ZIP 55733 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.

Zone4b−25 to −20 °F

Coldest night−31.7 to −28.9 °C

Last frostMay 26

First frostSep 23

2012 zone4a

Was 4a 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 4b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Esko, 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 Esko, MN

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 26median — 50% chance of a later frost

Safe for tender plantsJune 9only 10% chance of frost after

First fall frostSeptember 23median — 10% chance by Sep 9

Growing season118 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 12 and returns around October 3.

From the NOAA station Cloquet, MN — 7 miles away, elevation 1,266 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 55733

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 14 – Apr 28

SpinachSow outdoors · Apr 14 – May 5

Broccoli, cabbageStart indoors · Mar 17 – Mar 31

Broccoli, cabbageTransplant · May 5 – May 19

Onion setsPlant outdoors · Apr 28 – May 12

PotatoesPlant outdoors · May 5 – May 19

LettuceSow outdoors · Apr 28 – May 12

Carrots, beetsSow outdoors · May 5 – May 19

TomatoesStart indoors · Mar 31 – Apr 14

TomatoesTransplant · Jun 2 – Jun 16

Peppers, eggplantStart indoors · Mar 17 – Mar 31

Peppers, eggplantTransplant · Jun 9 – Jun 23

BeansSow outdoors · Jun 2 – Jun 16

Sweet cornSow outdoors · Jun 2 – Jun 16

Cucumbers, squashSow outdoors · Jun 2 – Jun 16

Fall lettuce, spinachSow outdoors · Jul 29 – Aug 12

GarlicPlant cloves · Sep 9 – Oct 14

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 26) and first fall frost (Sep 23) 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 55733 came on May 2 — 5 days later than the 1991–2020 average (Apr 27).

average
Apr 272026
May 2

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 Esko, MN

The soil mapped at the center of ZIP 55733 is Duluth — very fine sandy loam, well drained.

TextureVery fine sandy loamdrains and warms fast; dries out and needs more feeding

pH5.3strongly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter3%moderate

Hydrologic groupCwater soaks in slowly

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Duluth very fine sandy loam, 2 to 12 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 55733; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Esko, MN

Summer high79 °Faverage high, July

Winter low2 °Faverage low, January

Hot days6days a year at 90 °F or more

Freezing nights191nights a year at 32 °F or less

Growing degree days1,680base 50 °F — the season’s usable heat

Longest day15 h 51 mindaylight on June 21

Shortest day8 h 33 mindaylight on December 21

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

Precipitation32.7 inper year, rain and melted snow

Snowfall71 inper year; 138 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: Cloquet, MN (7 mi away); precipitation: Cloquet, MN (7 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

Wrenshall, MN · 10 mi

Minnesota planting zones →

Questions about 55733

What planting zone is ZIP code 55733?

ZIP code 55733 (Esko, MN) is in USDA hardiness zone 4b on the 2023 map: the coldest night of an average winter reaches −25 to −20 °F (−31.7 to −28.9 °C).

When is the last frost in Esko, MN?

The median last spring frost (32 °F) near 55733 is May 26; after June 9 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Cloquet station.

When is the first frost in Esko, MN?

The median first fall frost near 55733 is September 23, giving a median frost-free growing season of 118 days.

When should I plant tomatoes in 55733?

Start tomato seeds indoors around Mar 31 – Apr 14 and set transplants outside around Jun 2 – Jun 16, one to three weeks after the median last frost.

How much rain and snow does 55733 get?

About 32.7 inches of precipitation a year and 71 inches of snowfall (NOAA 1991–2020 normals, Cloquet station).

How hot do summers get in Esko, MN?

The average high peaks at 79 °F in July, with about 6 days a year at 90 °F or more.

What kind of soil does 55733 have?

The USDA soil survey maps Duluth at the center of ZIP 55733: very fine sandy loam, well drained, pH about 5.3 (strongly acidic).

Did spring come early in Esko, MN in 2026?

Spring leaf-out near 55733 came on May 2 in 2026, 5 days later than the 1991–2020 average (Apr 27), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Esko, MN?

Long-day onions: the longest day near 55733 is 15 h 51 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 55733 change?

Yes. The 2012 USDA map put 55733 in zone 4a; the 2023 map puts it in zone 4b. The newer map uses 1991–2020 data and more weather stations.