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

Planting zone for Ypsilanti, MI

Ypsilanti, MI is in USDA zone 6a across its 2 ZIP codes. The median last spring frost is May 5 and the first fall frost October 10.

Ypsilanti on the zone map

Outlined: its 2 ZIP code areas · 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
ZIP codes2
Last frostMay 5
First frostOct 10
Growing season157 days

6a 2 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Ypsilanti, 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 Ypsilanti, 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 20only 10% chance of frost after
First fall frostOctober 10median — 10% chance by Sep 28
Growing season157 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 24 and returns around October 23.

From the NOAA station Ann Arbor Se, MI, elevation 833 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 Ypsilanti

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 15 – Aug 29
GarlicPlant cloves · Sep 26 – Oct 31
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 5) and first fall frost (Oct 10) 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 48198 came on Mar 27 — 11 days earlier than the 1991–2020 average (Apr 7).

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 Ypsilanti, MI.

Soil in Ypsilanti, MI

The soil mapped at the center of ZIP 48198 is Matherton — sandy loam, somewhat poorly drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding
pH6.5neutral; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter3%moderate
Hydrologic groupB/Dmoderate when drained; wet otherwise
Farmland classPrime farmland if drainedUSDA classification

Map unit: Matherton sandy loam, 0 to 4 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 48198; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Ypsilanti, MI

Summer high86 °Faverage high, July
Winter low20 °Faverage low, January
Hot days21days a year at 90 °F or more
Freezing nights130nights a year at 32 °F or less
Growing degree days3,267base 50 °F — the season’s usable heat
Longest day15 h 16 mindaylight on June 21
Shortest day9 h 05 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation30.2 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 34 °F, low 20 °F 34°20° JanFebruary: average high 37 °F, low 21 °F 37°21° FebMarch: average high 48 °F, low 29 °F 48°29° MarApril: average high 61 °F, low 39 °F 61°39° AprMay: average high 73 °F, low 50 °F 73°50° MayJune: average high 82 °F, low 60 °F 82°60° JunJuly: average high 86 °F, low 63 °F 86°63° JulAugust: average high 84 °F, low 62 °F 84°62° AugSeptember: average high 77 °F, low 54 °F 77°54° SepOctober: average high 64 °F, low 43 °F 64°43° OctNovember: average high 50 °F, low 34 °F 50°34° NovDecember: average high 39 °F, low 26 °F 39°26° Dec

Precipitation by month inches

0″1″2″3″4″January: 1.68 in precipitation 1.7 JanFebruary: 1.45 in precipitation 1.4 FebMarch: 2.14 in precipitation 2.1 MarApril: 3.14 in precipitation 3.1 AprMay: 3.30 in precipitation 3.3 MayJune: 2.99 in precipitation 3.0 JunJuly: 2.98 in precipitation 3.0 JulAugust: 3.11 in precipitation 3.1 AugSeptember: 2.97 in precipitation 3.0 SepOctober: 2.53 in precipitation 2.5 OctNovember: 2.23 in precipitation 2.2 NovDecember: 1.67 in precipitation 1.7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Detroit Willow Run Airport, MI (4 mi away); precipitation: Detroit Willow Run Airport, MI (4 mi away). Daylight is calculated from latitude.

ZIP codes in Ypsilanti

Michigan planting zones →

Questions about Ypsilanti

What planting zone is Ypsilanti, MI?

Ypsilanti, MI is in USDA hardiness zone 6a on the 2023 map (6a: −10 to −5 °F).

When is the last frost in Ypsilanti, MI?

The median last spring frost is May 5 and the median first fall frost is October 10 (NOAA 1991–2020 normals, Ann Arbor Se station).

When can I plant a garden in Ypsilanti, MI?

Cool-season crops like peas and spinach go in around Mar 24 – Apr 14; tomatoes, peppers, beans and squash after about May 12, once frost risk has passed.

What kind of onions grow in Ypsilanti, MI?

Long-day onions: the longest day is 15 h 16 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

How much rain and snow does Ypsilanti, MI get?

About 30.2 inches of precipitation a year (NOAA 1991–2020 normals).