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

Planting zone for 48468 — Port Hope, MI

ZIP code 48468 (Port Hope, Huron County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 5 and the first fall frost October 24.

Where ZIP 48468 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.

Zone6a−10 to −5 °F
Coldest night−23.3 to −20.6 °C
Last frostMay 5
First frostOct 24
2012 zone6a

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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Port Hope, MI…

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 Port Hope, MI

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 24median — 10% chance by Oct 7
Growing season169 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 21 and returns around November 5.

From the NOAA station Port Hope, MI — 3 miles away, elevation 600 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 48468

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 29 – Sep 12
GarlicPlant cloves · Oct 10 – Nov 14
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 5) and first fall frost (Oct 24) 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 48468 came on Apr 16 — 4 days earlier than the 1991–2020 average (Apr 20).

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 6a in Michigan

580 plants native to the lower 48 states, recorded in Michigan, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 58

Shrubs 105

Wildflowers & perennials 220

Grasses 174

Vines 8

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 Port Hope, MI.

Soil in Port Hope, MI

The soil mapped at the center of ZIP 48468 is Corunna — sandy loam, poorly drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding
pH7.6slightly alkaline; most vegetables like 6.0–7.0
DrainagePoorly drainedconsider raised beds
Organic matter4%moderate
Hydrologic groupB/Dmoderate when drained; wet otherwise
Farmland classPrime farmland if drainedUSDA classification

Map unit: Corunna sandy loam.

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 48468; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Port Hope, MI

Summer high77 °Faverage high, July
Winter low16 °Faverage low, January
Hot days5days a year at 90 °F or more
Freezing nights140nights a year at 32 °F or less
Growing degree days2,088base 50 °F — the season’s usable heat
Longest day15 h 29 mindaylight on June 21
Shortest day8 h 53 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation30.4 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 28 °F, low 16 °F 28°16° JanFebruary: average high 30 °F, low 16 °F 30°16° FebMarch: average high 38 °F, low 24 °F 38°24° MarApril: average high 49 °F, low 33 °F 49°33° AprMay: average high 60 °F, low 44 °F 60°44° MayJune: average high 71 °F, low 54 °F 71°54° JunJuly: average high 77 °F, low 60 °F 77°60° JulAugust: average high 77 °F, low 59 °F 77°59° AugSeptember: average high 70 °F, low 52 °F 70°52° SepOctober: average high 57 °F, low 42 °F 57°42° OctNovember: average high 45 °F, low 32 °F 45°32° NovDecember: average high 34 °F, low 23 °F 34°23° Dec

Precipitation by month inches

0″1″2″3″4″January: 1.72 in precipitation 1.7 JanFebruary: 1.40 in precipitation 1.4 FebMarch: 2.06 in precipitation 2.1 MarApril: 2.98 in precipitation 3.0 AprMay: 2.92 in precipitation 2.9 MayJune: 2.49 in precipitation 2.5 JunJuly: 2.84 in precipitation 2.8 JulAugust: 3.42 in precipitation 3.4 AugSeptember: 2.92 in precipitation 2.9 SepOctober: 3.27 in precipitation 3.3 OctNovember: 2.37 in precipitation 2.4 NovDecember: 1.98 in precipitation 2.0 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Port Hope, MI (3 mi away); precipitation: Port Hope, MI (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

Michigan planting zones →

Questions about 48468

What planting zone is ZIP code 48468?

ZIP code 48468 (Port Hope, MI) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).

When is the last frost in Port Hope, MI?

The median last spring frost (32 °F) near 48468 is May 5; after May 21 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Port Hope station.

When is the first frost in Port Hope, MI?

The median first fall frost near 48468 is October 24, giving a median frost-free growing season of 169 days.

When should I plant tomatoes in 48468?

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 48468 get?

About 30.4 inches of precipitation a year (NOAA 1991–2020 normals, Port Hope station).

How hot do summers get in Port Hope, MI?

The average high peaks at 77 °F in July, with about 5 days a year at 90 °F or more.

What kind of soil does 48468 have?

The USDA soil survey maps Corunna at the center of ZIP 48468: sandy loam, poorly drained, pH about 7.6 (slightly alkaline).

Did spring come early in Port Hope, MI in 2026?

Spring leaf-out near 48468 came on Apr 16 in 2026, 4 days earlier than the 1991–2020 average (Apr 20), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Port Hope, MI?

Long-day onions: the longest day near 48468 is 15 h 29 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).