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

Planting zone for 55303 — Anoka, MN

ZIP code 55303 (Anoka, Anoka County) is in USDA zone 4b: the coldest winter night averages −25 to −20 °F. The median last spring frost is May 5 and the first fall frost October 2.

Where ZIP 55303 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 5
First frostOct 2
2012 zone4b

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 4b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Anoka, 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 Anoka, MN

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 5median — 50% chance of a later frost
Safe for tender plantsMay 21only 10% chance of frost after
First fall frostOctober 2median — 10% chance by Sep 18
Growing season148 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 25 and returns around October 13.

From the NOAA station Andover 1n, MN — 7 miles away, elevation 899 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 55303

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 24 – Apr 7
SpinachSow outdoors · Mar 24 – Apr 14
Broccoli, cabbageStart indoors · Feb 24 – Mar 10
Broccoli, cabbageTransplant · Apr 14 – Apr 28
Onion setsPlant outdoors · Apr 7 – Apr 21
PotatoesPlant outdoors · Apr 14 – Apr 28
LettuceSow outdoors · Apr 7 – Apr 21
Carrots, beetsSow outdoors · Apr 14 – Apr 28
TomatoesStart indoors · Mar 10 – Mar 24
TomatoesTransplant · May 12 – May 26
Peppers, eggplantStart indoors · Feb 24 – Mar 10
Peppers, eggplantTransplant · May 19 – Jun 2
BeansSow outdoors · May 12 – May 26
Sweet cornSow outdoors · May 12 – May 26
Cucumbers, squashSow outdoors · May 12 – May 26
Fall lettuce, spinachSow outdoors · Aug 7 – Aug 21
GarlicPlant cloves · Sep 18 – Oct 23
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 5) and first fall frost (Oct 2) 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 55303 came on Apr 11 — 6 days earlier than the 1991–2020 average (Apr 17).

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 4b in Minnesota

497 plants native to the lower 48 states, recorded in Minnesota, and rated by the USDA to survive −25 °F or colder — the bottom of zone 4b. Each links to its USDA PLANTS profile.

Trees 47

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 88

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 190

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 156

alkali cordgrass3 ft · blooms late summer · high shade tolerance · to −38 °FAmerican beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °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 °F

Vines 4

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 °FVirginia creeper1 ft · blooms late spring · medium shade tolerance · to −28 °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 Anoka, MN.

Soil in Anoka, MN

The soil mapped at the center of ZIP 55303 is Zimmerman — fine sand, somewhat excessively drained.

TextureFine sanddrains and warms fast; dries out and needs more feeding
pH6.0slightly acidic; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter1%low — add compost
Hydrologic groupAwater soaks in fast
Farmland classNot prime farmlandUSDA classification

Map unit: Zimmerman fine sand, 6 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 55303; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Anoka, MN

Summer high82 °Faverage high, July
Winter low2 °Faverage low, January
Hot days10days a year at 90 °F or more
Freezing nights172nights a year at 32 °F or less
Growing degree days2,396base 50 °F — the season’s usable heat
Longest day15 h 39 mindaylight on June 21
Shortest day8 h 44 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation28.8 inper year, rain and melted snow
Snowfall44 inper year; 106 days with snow on the ground

Average high and low, by month

−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 22 °F, low 2 °F 22°2° JanFebruary: average high 28 °F, low 7 °F 28°7° FebMarch: average high 41 °F, low 19 °F 41°19° MarApril: average high 56 °F, low 32 °F 56°32° AprMay: average high 68 °F, low 45 °F 68°45° MayJune: average high 78 °F, low 55 °F 78°55° JunJuly: average high 82 °F, low 60 °F 82°60° JulAugust: average high 80 °F, low 57 °F 80°57° AugSeptember: average high 72 °F, low 48 °F 72°48° SepOctober: average high 58 °F, low 36 °F 58°36° OctNovember: average high 41 °F, low 23 °F 41°23° NovDecember: average high 27 °F, low 11 °F 27°11° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 0.57 in precipitation, 5.1 in snowfall 0.6❄5 JanFebruary: 0.83 in precipitation, 9.6 in snowfall 0.8❄10 FebMarch: 1.44 in precipitation, 6.3 in snowfall 1.4❄6 MarApril: 2.94 in precipitation, 5.7 in snowfall 2.9❄6 AprMay: 3.57 in precipitation 3.6 MayJune: 3.80 in precipitation 3.8 JunJuly: 4.46 in precipitation 4.5 JulAugust: 3.60 in precipitation 3.6 AugSeptember: 2.53 in precipitation 2.5 SepOctober: 2.69 in precipitation, 0.7 in snowfall 2.7❄1 OctNovember: 1.38 in precipitation, 4.3 in snowfall 1.4❄4 NovDecember: 1.01 in precipitation, 12.4 in snowfall 1.0❄12 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Andover 1n, MN (7 mi away); precipitation: Andover 1n, MN (7 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

553274b
Dayton, MN · 6 mi
553304b
Elk River, MN · 7 mi
553165a
Champlin, MN · 8 mi
553044b
Andover, MN · 9 mi
554485a
Minneapolis, MN · 9 mi
550114b
Cedar, MN · 10 mi
550704b
Saint Francis, MN · 10 mi
553744b
Rogers, MN · 10 mi

Minnesota planting zones →

Questions about 55303

What planting zone is ZIP code 55303?

ZIP code 55303 (Anoka, 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 Anoka, MN?

The median last spring frost (32 °F) near 55303 is May 5; after May 21 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Andover 1n station.

When is the first frost in Anoka, MN?

The median first fall frost near 55303 is October 2, giving a median frost-free growing season of 148 days.

When should I plant tomatoes in 55303?

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

How much rain and snow does 55303 get?

About 28.8 inches of precipitation a year and 44 inches of snowfall (NOAA 1991–2020 normals, Andover 1n station).

How hot do summers get in Anoka, MN?

The average high peaks at 82 °F in July, with about 10 days a year at 90 °F or more.

What kind of soil does 55303 have?

The USDA soil survey maps Zimmerman at the center of ZIP 55303: fine sand, somewhat excessively drained, pH about 6.0 (slightly acidic).

Did spring come early in Anoka, MN in 2026?

Spring leaf-out near 55303 came on Apr 11 in 2026, 6 days earlier than the 1991–2020 average (Apr 17), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Anoka, MN?

Long-day onions: the longest day near 55303 is 15 h 39 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).