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

Planting zone for 49834 — Foster City, MI

ZIP code 49834 (Foster City, Dickinson County) is in USDA zone 4b: the coldest winter night averages −25 to −20 °F. The median last spring frost is May 17 and the first fall frost October 1.

Where ZIP 49834 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 17
First frostOct 1
2012 zone4a

Was 4a 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 4b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Foster City, 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 Foster City, MI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 17median — 50% chance of a later frost
Safe for tender plantsMay 31only 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 4 and returns around October 11.

From the NOAA station Iron Mtn-Kingsford Wwtp, MI — 22 miles away, elevation 1,070 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 49834

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 5 – Apr 19
SpinachSow outdoors · Apr 5 – Apr 26
Broccoli, cabbageStart indoors · Mar 8 – Mar 22
Broccoli, cabbageTransplant · Apr 26 – May 10
Onion setsPlant outdoors · Apr 19 – May 3
PotatoesPlant outdoors · Apr 26 – May 10
LettuceSow outdoors · Apr 19 – May 3
Carrots, beetsSow outdoors · Apr 26 – May 10
TomatoesStart indoors · Mar 22 – Apr 5
TomatoesTransplant · May 24 – Jun 7
Peppers, eggplantStart indoors · Mar 8 – Mar 22
Peppers, eggplantTransplant · May 31 – Jun 14
BeansSow outdoors · May 24 – Jun 7
Sweet cornSow outdoors · May 24 – Jun 7
Cucumbers, squashSow outdoors · May 24 – Jun 7
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 17) 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 49834 came on Apr 25 — about the same time as the 1991–2020 average (Apr 26).

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 Michigan

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

Trees 51

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 97

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 °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 157

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 5

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 °Ftrumpet honeysuckle16 ft · blooms late summer · low 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 Foster City, MI.

Soil in Foster City, MI

The soil mapped at the center of ZIP 49834 is Emmet — highly decomposed plant material, well drained.

TextureHighly decomposed plant materialtop layer
pH6.0slightly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter75%high
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Emmet fine sandy loam, drumlins, 6 to 18 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 49834; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Foster City, MI

Summer high80 °Faverage high, July
Winter low4 °Faverage low, January
Hot days6days a year at 90 °F or more
Freezing nights182nights a year at 32 °F or less
Growing degree days2,062base 50 °F — the season’s usable heat
Longest day15 h 45 mindaylight on June 21
Shortest day8 h 38 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation31.3 inper year, rain and melted snow
Snowfall70 inper year

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 6 °F 28°6° FebMarch: average high 39 °F, low 17 °F 39°17° MarApril: average high 52 °F, low 29 °F 52°29° AprMay: average high 66 °F, low 42 °F 66°42° MayJune: average high 76 °F, low 52 °F 76°52° JunJuly: average high 80 °F, low 57 °F 80°57° JulAugust: average high 78 °F, low 55 °F 78°55° AugSeptember: average high 70 °F, low 47 °F 70°47° SepOctober: average high 56 °F, low 35 °F 56°35° OctNovember: average high 41 °F, low 24 °F 41°24° NovDecember: average high 29 °F, low 13 °F 29°13° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″January: 1.54 in precipitation, 18.1 in snowfall 1.5❄18 JanFebruary: 1.27 in precipitation, 11 in snowfall 1.3❄11 FebMarch: 1.85 in precipitation, 12.1 in snowfall 1.9❄12 MarApril: 3.27 in precipitation, 7.7 in snowfall 3.3❄8 AprMay: 3.42 in precipitation, 0.2 in snowfall 3.4 MayJune: 2.91 in precipitation 2.9 JunJuly: 3.62 in precipitation 3.6 JulAugust: 2.75 in precipitation 2.8 AugSeptember: 3.54 in precipitation 3.5 SepOctober: 2.97 in precipitation, 0.7 in snowfall 3.0❄1 OctNovember: 2.31 in precipitation, 7.4 in snowfall 2.3❄7 NovDecember: 1.81 in precipitation, 13 in snowfall 1.8❄13 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Iron Mtn-Kingsford Wwtp, MI (22 mi away); precipitation: Spalding 1 Nw, MI (20 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.

498314b
Felch, MI · 6 mi
498704b
Norway, MI · 11 mi
498774b
Ralph, MI · 13 mi
498525a
Loretto, MI · 14 mi
498925a
Vulcan, MI · 14 mi
498735a
Perronville, MI · 14 mi
498185a
Cornell, MI · 17 mi
498764b
Quinnesec, MI · 17 mi

Michigan planting zones →

Questions about 49834

What planting zone is ZIP code 49834?

ZIP code 49834 (Foster City, MI) 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 Foster City, MI?

The median last spring frost (32 °F) near 49834 is May 17; after May 31 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Iron Mtn-Kingsford Wwtp station.

When is the first frost in Foster City, MI?

The median first fall frost near 49834 is October 1, giving a median frost-free growing season of 135 days.

When should I plant tomatoes in 49834?

Start tomato seeds indoors around Mar 22 – Apr 5 and set transplants outside around May 24 – Jun 7, one to three weeks after the median last frost.

How much rain and snow does 49834 get?

About 31.3 inches of precipitation a year and 70 inches of snowfall (NOAA 1991–2020 normals, Spalding 1 Nw station).

How hot do summers get in Foster City, MI?

The average high peaks at 80 °F in July, with about 6 days a year at 90 °F or more.

What kind of soil does 49834 have?

The USDA soil survey maps Emmet at the center of ZIP 49834: highly decomposed plant material, well drained, pH about 6.0 (slightly acidic).

Did spring come early in Foster City, MI in 2026?

Spring leaf-out near 49834 came on Apr 25 in 2026, about the same as the 1991–2020 average (Apr 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Foster City, MI?

Long-day onions: the longest day near 49834 is 15 h 45 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 49834 change?

Yes. The 2012 USDA map put 49834 in zone 4a; the 2023 map puts it in zone 4b. The newer map uses 1991–2020 data and more weather stations.