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

Planting zone for 56330 — Foreston, MN

ZIP code 56330 (Foreston, Mille Lacs County) is in USDA zone 4a: the coldest winter night averages −30 to −25 °F. The median last spring frost is May 8 and the first fall frost October 1.

Where ZIP 56330 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 8
First frostOct 1
2012 zone4a

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 4a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Foreston, 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 Foreston, MN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 8median — 50% chance of a later frost
Safe for tender plantsMay 26only 10% chance of frost after
First fall frostOctober 1median — 10% chance by Sep 17
Growing season143 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 28 and returns around October 11.

From the NOAA station Milaca, MN — 4 miles away, elevation 1,063 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 56330

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 27 – Apr 10
SpinachSow outdoors · Mar 27 – Apr 17
Broccoli, cabbageStart indoors · Feb 27 – Mar 13
Broccoli, cabbageTransplant · Apr 17 – May 1
Onion setsPlant outdoors · Apr 10 – Apr 24
PotatoesPlant outdoors · Apr 17 – May 1
LettuceSow outdoors · Apr 10 – Apr 24
Carrots, beetsSow outdoors · Apr 17 – May 1
TomatoesStart indoors · Mar 13 – Mar 27
TomatoesTransplant · May 15 – May 29
Peppers, eggplantStart indoors · Feb 27 – Mar 13
Peppers, eggplantTransplant · May 22 – Jun 5
BeansSow outdoors · May 15 – May 29
Sweet cornSow outdoors · May 15 – May 29
Cucumbers, squashSow outdoors · May 15 – May 29
Fall lettuce, spinachSow outdoors · Aug 6 – Aug 20
GarlicPlant cloves · Sep 17 – Oct 22
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 8) and first fall frost (Oct 1) 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 56330 came on Apr 17 — 4 days earlier than the 1991–2020 average (Apr 21).

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

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °Farborvitae50 ft · blooms mid spring · medium shade tolerance · to −33 °Fbalsam fir60 ft · blooms mid summer · low shade tolerance · to −43 °Fbalsam poplar80 ft · blooms late spring · high shade tolerance · to −79 °F

Shrubs 77

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican hornbeam30 ft · blooms mid spring · low shade tolerance · to −34 °F

Wildflowers & perennials 173

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °F

Grasses 140

alkali cordgrass3 ft · blooms late summer · high shade tolerance · to −38 °Farctic brome3 ft · blooms early summer · low shade tolerance · to −33 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °Fbasin wildrye5 ft · blooms early spring · high shade tolerance · to −43 °Fbeaked sedge4 ft · blooms late spring · low shade tolerance · to −38 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °F

Vines 3

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °F

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 Foreston, MN.

Soil in Foreston, MN

The soil mapped at the center of ZIP 56330 is Cebana — silt loam, poorly drained.

TextureSilt loama good balance for most vegetables
pH6.0slightly acidic; most vegetables like 6.0–7.0
DrainagePoorly drainedconsider raised beds
Organic matter6%high
Hydrologic groupB/Dmoderate when drained; wet otherwise
Farmland classNot prime farmlandUSDA classification

Map unit: Cebana-Giese, frequently ponded-Freer complex, 0 to 3 percent slopes, stony.

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 56330; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Foreston, MN

Summer high80 °Faverage high, July
Winter low1 °Faverage low, January
Hot days5days a year at 90 °F or more
Freezing nights178nights a year at 32 °F or less
Growing degree days2,122base 50 °F — the season’s usable heat
Longest day15 h 43 mindaylight on June 21
Shortest day8 h 40 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation30.8 inper year, rain and melted snow
Snowfall49 inper year

Average high and low, by month

−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 20 °F, low 1 °F 20°1° JanFebruary: average high 26 °F, low 4 °F 26°4° FebMarch: average high 38 °F, low 17 °F 38°17° MarApril: average high 53 °F, low 30 °F 53°30° AprMay: average high 66 °F, low 43 °F 66°43° MayJune: average high 76 °F, low 54 °F 76°54° JunJuly: average high 80 °F, low 59 °F 80°59° JulAugust: average high 78 °F, low 56 °F 78°56° AugSeptember: average high 70 °F, low 46 °F 70°46° SepOctober: average high 56 °F, low 34 °F 56°34° OctNovember: average high 39 °F, low 21 °F 39°21° NovDecember: average high 26 °F, low 9 °F 26°9° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 0.77 in precipitation, 7.4 in snowfall 0.8❄7 JanFebruary: 0.85 in precipitation, 11.1 in snowfall 0.8❄11 FebMarch: 1.43 in precipitation, 8.4 in snowfall 1.4❄8 MarApril: 2.74 in precipitation, 4.4 in snowfall 2.7❄4 AprMay: 3.82 in precipitation, 0.1 in snowfall 3.8 MayJune: 4.31 in precipitation 4.3 JunJuly: 4.39 in precipitation 4.4 JulAugust: 3.97 in precipitation 4.0 AugSeptember: 3.19 in precipitation 3.2 SepOctober: 2.82 in precipitation, 0.8 in snowfall 2.8❄1 OctNovember: 1.41 in precipitation, 6.5 in snowfall 1.4❄7 NovDecember: 1.11 in precipitation, 10.2 in snowfall 1.1❄10 Dec

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

Nearby ZIP codes

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

563574b
Oak Park, MN · 5 mi
563634b
Pease, MN · 6 mi
563534a
Milaca, MN · 7 mi
563294a
Foley, MN · 8 mi
563134a
Bock, MN · 10 mi
553714b
Princeton, MN · 15 mi
553774b
Santiago, MN · 15 mi
563334a
Gilman, MN · 15 mi

Minnesota planting zones →

Questions about 56330

What planting zone is ZIP code 56330?

ZIP code 56330 (Foreston, 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 Foreston, MN?

The median last spring frost (32 °F) near 56330 is May 8; after May 26 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Milaca station.

When is the first frost in Foreston, MN?

The median first fall frost near 56330 is October 1, giving a median frost-free growing season of 143 days.

When should I plant tomatoes in 56330?

Start tomato seeds indoors around Mar 13 – Mar 27 and set transplants outside around May 15 – May 29, one to three weeks after the median last frost.

How much rain and snow does 56330 get?

About 30.8 inches of precipitation a year and 49 inches of snowfall (NOAA 1991–2020 normals, Milaca station).

How hot do summers get in Foreston, MN?

The average high peaks at 80 °F in July, with about 5 days a year at 90 °F or more.

What kind of soil does 56330 have?

The USDA soil survey maps Cebana at the center of ZIP 56330: silt loam, poorly drained, pH about 6.0 (slightly acidic).

Did spring come early in Foreston, MN in 2026?

Spring leaf-out near 56330 came on Apr 17 in 2026, 4 days earlier than the 1991–2020 average (Apr 21), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Foreston, MN?

Long-day onions: the longest day near 56330 is 15 h 43 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).