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

Planting zone for 52149 — Highlandville, IA

ZIP code 52149 (Highlandville, Winneshiek County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is May 10 and the first fall frost September 28.

Where ZIP 52149 is

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.

Zone5a−20 to −15 °F
Coldest night−28.9 to −26.1 °C
Last frostMay 10
First frostSep 28
2012 zone4b

Was 4b 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 5a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Highlandville, IA…

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 Highlandville, IA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 10median — 50% chance of a later frost
Safe for tender plantsMay 23only 10% chance of frost after
First fall frostSeptember 28median — 10% chance by Sep 14
Growing season140 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 1 and returns around October 6.

From the NOAA station Mabel, MN — 6 miles away, elevation 1,112 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 52149

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 29 – Apr 12
SpinachSow outdoors · Mar 29 – Apr 19
Broccoli, cabbageStart indoors · Mar 1 – Mar 15
Broccoli, cabbageTransplant · Apr 19 – May 3
Onion setsPlant outdoors · Apr 12 – Apr 26
PotatoesPlant outdoors · Apr 19 – May 3
LettuceSow outdoors · Apr 12 – Apr 26
Carrots, beetsSow outdoors · Apr 19 – May 3
TomatoesStart indoors · Mar 15 – Mar 29
TomatoesTransplant · May 17 – May 31
Peppers, eggplantStart indoors · Mar 1 – Mar 15
Peppers, eggplantTransplant · May 24 – Jun 7
BeansSow outdoors · May 17 – May 31
Sweet cornSow outdoors · May 17 – May 31
Cucumbers, squashSow outdoors · May 17 – May 31
Fall lettuce, spinachSow outdoors · Aug 3 – Aug 17
GarlicPlant cloves · Sep 14 – Oct 19
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 10) and first fall frost (Sep 28) 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 52149 came on Mar 30 — 15 days earlier than the 1991–2020 average (Apr 14).

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 5a in Iowa

461 plants native to the lower 48 states, recorded in Iowa, and rated by the USDA to survive −20 °F or colder — the bottom of zone 5a. Each links to its USDA PLANTS profile.

Trees 46

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican chestnut115 ft · blooms early summer · high shade tolerance · to −33 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Farborvitae50 ft · blooms mid spring · medium shade tolerance · to −33 °Fbalsam fir60 ft · blooms mid summer · low shade tolerance · to −43 °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 185

alkali buttercup1 ft · blooms late spring · low 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 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °F

Grasses 133

arctic brome3 ft · blooms early summer · low shade tolerance · to −33 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °FBicknell's sedge3 ft · blooms late spring · low shade tolerance · to −38 °Fbig bluestem6 ft · blooms summer · high shade tolerance · to −46 °Fblue grama1 ft · blooms early summer · high shade tolerance · to −43 °F

Vines 7

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Ffrost grape83 ft · blooms late spring · medium shade tolerance · to −23 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °Ftrumpet honeysuckle16 ft · blooms late summer · low 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 Highlandville, IA.

Soil in Highlandville, IA

The soil mapped at the center of ZIP 52149 is Tama — silt loam, well drained.

TextureSilt loama good balance for most vegetables
pH6.2slightly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3.5%moderate
Hydrologic groupCwater soaks in slowly
Farmland classprime farmlandUSDA classification

Map unit: Tama-Downs complex, driftless, 2 to 6 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 52149; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Highlandville, IA

Summer high80 °Faverage high, July
Winter low4 °Faverage low, January
Hot days2days a year at 90 °F or more
Freezing nights176nights a year at 32 °F or less
Growing degree days2,193base 50 °F — the season’s usable heat
Longest day15 h 25 mindaylight on June 21
Shortest day8 h 57 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation38.6 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 24 °F, low 4 °F 24°4° JanFebruary: average high 28 °F, low 7 °F 28°7° FebMarch: average high 40 °F, low 20 °F 40°20° MarApril: average high 55 °F, low 32 °F 55°32° AprMay: average high 67 °F, low 44 °F 67°44° MayJune: average high 76 °F, low 55 °F 76°55° JunJuly: average high 80 °F, low 58 °F 80°58° JulAugust: average high 78 °F, low 55 °F 78°55° AugSeptember: average high 72 °F, low 47 °F 72°47° SepOctober: average high 58 °F, low 35 °F 58°35° OctNovember: average high 43 °F, low 23 °F 43°23° NovDecember: average high 30 °F, low 12 °F 30°12° Dec

Precipitation by month inches

0″2″4″6″January: 1.00 in precipitation 1.0 JanFebruary: 1.01 in precipitation 1.0 FebMarch: 1.90 in precipitation 1.9 MarApril: 3.90 in precipitation 3.9 AprMay: 4.78 in precipitation 4.8 MayJune: 6.14 in precipitation 6.1 JunJuly: 4.47 in precipitation 4.5 JulAugust: 4.59 in precipitation 4.6 AugSeptember: 4.37 in precipitation 4.4 SepOctober: 3.13 in precipitation 3.1 OctNovember: 1.89 in precipitation 1.9 NovDecember: 1.40 in precipitation 1.4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Mabel, MN (6 mi away); precipitation: Mabel, MN (6 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.

559544b
Mabel, MN · 8 mi
521405a
Dorchester, IA · 8 mi
521015a
Decorah, IA · 8 mi
559745a
Spring Grove, MN · 8 mi
559224b
Canton, MN · 12 mi
559215a
Caledonia, MN · 15 mi
559315a
Eitzen, MN · 16 mi
521725a
Waukon, IA · 17 mi

Iowa planting zones →

Questions about 52149

What planting zone is ZIP code 52149?

ZIP code 52149 (Highlandville, IA) is in USDA hardiness zone 5a on the 2023 map: the coldest night of an average winter reaches −20 to −15 °F (−28.9 to −26.1 °C).

When is the last frost in Highlandville, IA?

The median last spring frost (32 °F) near 52149 is May 10; after May 23 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Mabel station.

When is the first frost in Highlandville, IA?

The median first fall frost near 52149 is September 28, giving a median frost-free growing season of 140 days.

When should I plant tomatoes in 52149?

Start tomato seeds indoors around Mar 15 – Mar 29 and set transplants outside around May 17 – May 31, one to three weeks after the median last frost.

How much rain and snow does 52149 get?

About 38.6 inches of precipitation a year (NOAA 1991–2020 normals, Mabel station).

How hot do summers get in Highlandville, IA?

The average high peaks at 80 °F in July, with about 2 days a year at 90 °F or more.

What kind of soil does 52149 have?

The USDA soil survey maps Tama at the center of ZIP 52149: silt loam, well drained, pH about 6.2 (slightly acidic).

Did spring come early in Highlandville, IA in 2026?

Spring leaf-out near 52149 came on Mar 30 in 2026, 15 days earlier than the 1991–2020 average (Apr 14), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Highlandville, IA?

Long-day onions: the longest day near 52149 is 15 h 25 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 52149 change?

Yes. The 2012 USDA map put 52149 in zone 4b; the 2023 map puts it in zone 5a. The newer map uses 1991–2020 data and more weather stations.