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

Planting zone for 49618 — Boon, MI

ZIP code 49618 (Boon, Wexford County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is May 19 and the first fall frost October 1.

Where ZIP 49618 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.

Zone5a−20 to −15 °F
Coldest night−28.9 to −26.1 °C
Last frostMay 19
First frostOct 1
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 Boon, 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 Boon, MI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 19median — 50% chance of a later frost
Safe for tender plantsJune 3only 10% chance of frost after
First fall frostOctober 1median — 10% chance by Sep 17
Growing season135 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 5 and returns around October 13.

From the NOAA station Cadillac, MI — 10 miles away, elevation 1,296 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 49618

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 7 – Apr 21
SpinachSow outdoors · Apr 7 – Apr 28
Broccoli, cabbageStart indoors · Mar 10 – Mar 24
Broccoli, cabbageTransplant · Apr 28 – May 12
Onion setsPlant outdoors · Apr 21 – May 5
PotatoesPlant outdoors · Apr 28 – May 12
LettuceSow outdoors · Apr 21 – May 5
Carrots, beetsSow outdoors · Apr 28 – May 12
TomatoesStart indoors · Mar 24 – Apr 7
TomatoesTransplant · May 26 – Jun 9
Peppers, eggplantStart indoors · Mar 10 – Mar 24
Peppers, eggplantTransplant · Jun 2 – Jun 16
BeansSow outdoors · May 26 – Jun 9
Sweet cornSow outdoors · May 26 – Jun 9
Cucumbers, squashSow outdoors · May 26 – Jun 9
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 19) 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 49618 came on Apr 16 — 5 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 5a in Michigan

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

Trees 54

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °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 °F

Shrubs 103

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 207

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °Falpine sweetvetch2 ft · blooms early summer · high shade tolerance · to −62 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °F

Grasses 166

alpine timothy1.4 ft · blooms late spring · medium shade tolerance · to −43 °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 °Fbeaked sedge4 ft · blooms late spring · low shade tolerance · to −38 °Fbeaked spikerush3 ft · blooms late spring · high shade tolerance · to −28 °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 Boon, MI.

Soil in Boon, MI

The soil mapped at the center of ZIP 49618 is Kalkaska — sand, somewhat excessively drained.

TextureSanddrains and warms fast; dries out and needs more feeding
pH5.6moderately acidic; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter2.5%moderate
Hydrologic groupAwater soaks in fast
Farmland classNot prime farmlandUSDA classification

Map unit: Kalkaska-East Lake sands, 12 to 30 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 49618; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Boon, MI

Summer high80 °Faverage high, July
Winter low12 °Faverage low, January
Hot days4days a year at 90 °F or more
Freezing nights172nights a year at 32 °F or less
Growing degree days2,137base 50 °F — the season’s usable heat
Longest day15 h 32 mindaylight on June 21
Shortest day8 h 51 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation35.2 inper year, rain and melted snow

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 27 °F, low 12 °F 27°12° JanFebruary: average high 30 °F, low 13 °F 30°13° FebMarch: average high 40 °F, low 20 °F 40°20° MarApril: average high 53 °F, low 31 °F 53°31° AprMay: average high 66 °F, low 43 °F 66°43° MayJune: average high 76 °F, low 53 °F 76°53° JunJuly: average high 80 °F, low 58 °F 80°58° JulAugust: average high 78 °F, low 55 °F 78°55° AugSeptember: average high 70 °F, low 48 °F 70°48° SepOctober: average high 56 °F, low 37 °F 56°37° OctNovember: average high 43 °F, low 28 °F 43°28° NovDecember: average high 32 °F, low 20 °F 32°20° Dec

Precipitation by month inches

0″1″2″3″4″January: 2.05 in precipitation 2.0 JanFebruary: 1.53 in precipitation 1.5 FebMarch: 2.06 in precipitation 2.1 MarApril: 3.56 in precipitation 3.6 AprMay: 3.63 in precipitation 3.6 MayJune: 3.61 in precipitation 3.6 JunJuly: 3.46 in precipitation 3.5 JulAugust: 3.50 in precipitation 3.5 AugSeptember: 3.16 in precipitation 3.2 SepOctober: 3.86 in precipitation 3.9 OctNovember: 2.72 in precipitation 2.7 NovDecember: 2.02 in precipitation 2.0 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Cadillac, MI (10 mi away); precipitation: Cadillac, MI (10 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

496015a
Cadillac, MI · 5 mi
496385b
Harrietta, MI · 8 mi
496685b
Mesick, MI · 9 mi
496635b
Manton, MI · 13 mi
496885a
Tustin, MI · 14 mi
496205b
Buckley, MI · 16 mi
496255b
Copemish, MI · 16 mi
496895b
Wellston, MI · 17 mi

Michigan planting zones →

Questions about 49618

What planting zone is ZIP code 49618?

ZIP code 49618 (Boon, MI) 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 Boon, MI?

The median last spring frost (32 °F) near 49618 is May 19; after June 3 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Cadillac station.

When is the first frost in Boon, MI?

The median first fall frost near 49618 is October 1, giving a median frost-free growing season of 135 days.

When should I plant tomatoes in 49618?

Start tomato seeds indoors around Mar 24 – Apr 7 and set transplants outside around May 26 – Jun 9, one to three weeks after the median last frost.

How much rain and snow does 49618 get?

About 35.2 inches of precipitation a year (NOAA 1991–2020 normals, Cadillac station).

How hot do summers get in Boon, MI?

The average high peaks at 80 °F in July, with about 4 days a year at 90 °F or more.

What kind of soil does 49618 have?

The USDA soil survey maps Kalkaska at the center of ZIP 49618: sand, somewhat excessively drained, pH about 5.6 (moderately acidic).

Did spring come early in Boon, MI in 2026?

Spring leaf-out near 49618 came on Apr 16 in 2026, 5 days earlier than the 1991–2020 average (Apr 21), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Boon, MI?

Long-day onions: the longest day near 49618 is 15 h 32 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 49618 change?

Yes. The 2012 USDA map put 49618 in zone 4b; the 2023 map puts it in zone 5a. The newer map uses 1991–2020 data and more weather stations.