State guide
Planting zones in Michigan
Michigan spans USDA zones 4a to 7a across its 991 ZIP codes, so there is no single zone for the state and anyone who gives you one is rounding. 54% of its ZIP codes are zone 6a; the rest are not.
Your ZIP code
Get the exact answer for your address
Everything above describes Michigan as a whole. Hardiness zones and freeze dates are published per ZIP code, so yours is exact — enter it and this page will tell you your zone, which NOAA station it comes from and how far away that station is.
Which zone you are in depends where you are
Michigan covers 7 hardiness zones. A guide that gives the state one zone has picked whichever is largest and rounded everyone else into it — which is fine for the 54% in zone 6a and wrong for the other 46%. Here is the actual split, by ZIP code.
| Zone | ZIP codes | Share | |
|---|---|---|---|
| 6a | 532 | 54% | |
| 6b | 180 | 18% | |
| 5a | 125 | 13% | |
| 5b | 104 | 10% | |
| 4b | 37 | 4% | |
| 4a | 12 | 1% | |
| 7a | 1 | 0% |
Zones are published per ZIP code, so yours is exact even though the state's is not. The hardiness tool will tell you which one you are in.
Your freeze dates
Those are the earliest and latest medians among the 211 stations in Michigan with an ordinary freeze window — not an average, and not one station standing in for the rest. Half of years freeze later than a station's own median.
Your growing season
NOAA publishes a growing-season length for each station, and across the 211 stations in Michigan it runs 94–201 days . That figure is published, not computed from the two freeze dates — subtracting one from the other gives the wrong answer wherever a season crosses New Year. Mean summer high (June–August) runs 71–84 °F , below the 90 °F point where cool-season crops reliably bolt.
The ends of each range, named
A range with no station behind it cannot be checked, and Michigan has too many stations to table them all. So every figure above is reported here with the station standing at each end of it, by name and NOAA ID. No station on this page represents Michigan — these are its edges, which is a different claim.
| Measure | Earliest / lowest | Station | Latest / highest | Station |
|---|---|---|---|---|
| Last spring freeze | April 17 | S Haven, MI USC00207690 | June 7 | Vanderbilt 11Ene, MI USC00208417 |
| First fall freeze | September 9 | Amasa 1W, MI USC00200197 | November 5 | S Haven, MI USC00207690 |
| Growing season | 94 days | Amasa 1W, MI USC00200197 | 201 days | S Haven, MI USC00207690 |
| Mean summer high | 71 °F | Copper Harbor, MI USW00094899 | 84 °F | Detroit Willow Run AP, MI USW00014853 |
These are medians, not averages — NOAA publishes freeze dates as a probability distribution, and half of years freeze later than the date shown.
When to start seeds in Michigan
Every spring job for 63 crop dates, counted from this state's own last spring freeze. Each is a range across all 211 stations — the earliest and latest that job falls anywhere in Michigan — because no one station speaks for a whole state. The ranges are wide on purpose: that width is the state.
| Crop | Job | When | Offset |
|---|---|---|---|
| Green Onions | Start indoors | February 20 – April 12 | 8 weeks before |
| Peppers | Start indoors | February 20 – April 12 | 8 weeks before |
| Broccoli | Start indoors | March 6 – April 26 | 6 weeks before |
| Cabbage | Start indoors | March 6 – April 26 | 6 weeks before |
| Collards | Start indoors | March 6 – April 26 | 6 weeks before |
| Kale | Start indoors | March 6 – April 26 | 6 weeks before |
| Leaf Lettuce | Start indoors | March 6 – April 26 | 6 weeks before |
| Peas | Direct sow | March 6 – April 26 | 6 weeks before |
| Spinach | Direct sow | March 6 – April 26 | 6 weeks before |
| Sweet Potato | Start indoors | March 6 – April 26 | 6 weeks before |
| Tomatoes | Start indoors | March 6 – April 26 | 6 weeks before |
| Bok Choy | Start indoors | March 13 – May 3 | 5 weeks before |
| Kohlrabi | Start indoors | March 13 – May 3 | 5 weeks before |
| Swiss Chard | Start indoors | March 13 – May 3 | 5 weeks before |
| Arugula | Direct sow | March 20 – May 10 | 4 weeks before |
| Baby Salad Greens | Direct sow | March 20 – May 10 | 4 weeks before |
| Beets | Direct sow | March 20 – May 10 | 4 weeks before |
| Green Onions | Direct sow | March 20 – May 10 | 4 weeks before |
| Mustard Greens | Direct sow | March 20 – May 10 | 4 weeks before |
| Okra | Start indoors | March 20 – May 10 | 4 weeks before |
| Radishes | Direct sow | March 20 – May 10 | 4 weeks before |
| Turnips | Direct sow | March 20 – May 10 | 4 weeks before |
| Cabbage | Set out | March 27 – May 17 | 3 weeks before |
| Carrots | Direct sow | March 27 – May 17 | 3 weeks before |
| Collards | Direct sow | March 27 – May 17 | 3 weeks before |
| Collards | Set out | March 27 – May 17 | 3 weeks before |
| Cucumbers | Start indoors | March 27 – May 17 | 3 weeks before |
| Green Onions | Set out | March 27 – May 17 | 3 weeks before |
| Kale | Direct sow | March 27 – May 17 | 3 weeks before |
| Kale | Set out | March 27 – May 17 | 3 weeks before |
| Kohlrabi | Direct sow | March 27 – May 17 | 3 weeks before |
| Kohlrabi | Set out | March 27 – May 17 | 3 weeks before |
| Leaf Lettuce | Direct sow | March 27 – May 17 | 3 weeks before |
| Pumpkins | Start indoors | March 27 – May 17 | 3 weeks before |
| Summer Squash | Start indoors | March 27 – May 17 | 3 weeks before |
| Winter Squash | Start indoors | March 27 – May 17 | 3 weeks before |
| Zucchini | Start indoors | March 27 – May 17 | 3 weeks before |
| Bok Choy | Direct sow | April 3 – May 24 | 2 weeks before |
| Bok Choy | Set out | April 3 – May 24 | 2 weeks before |
| Broccoli | Set out | April 3 – May 24 | 2 weeks before |
| Cilantro | Direct sow | April 3 – May 24 | 2 weeks before |
| Leaf Lettuce | Set out | April 3 – May 24 | 2 weeks before |
| Swiss Chard | Direct sow | April 3 – May 24 | 2 weeks before |
| Swiss Chard | Set out | April 3 – May 24 | 2 weeks before |
| Dill | Direct sow | April 10 – May 31 | 1 week before |
| Bush Beans | Direct sow | April 24 – June 14 | 1 week after |
| Cucumbers | Set out | April 24 – June 14 | 1 week after |
| Pumpkins | Direct sow | April 24 – June 14 | 1 week after |
| Pumpkins | Set out | April 24 – June 14 | 1 week after |
| Summer Squash | Direct sow | April 24 – June 14 | 1 week after |
| Summer Squash | Set out | April 24 – June 14 | 1 week after |
| Sweet Corn | Direct sow | April 24 – June 14 | 1 week after |
| Tomatoes | Set out | April 24 – June 14 | 1 week after |
| Winter Squash | Direct sow | April 24 – June 14 | 1 week after |
| Winter Squash | Set out | April 24 – June 14 | 1 week after |
| Zucchini | Direct sow | April 24 – June 14 | 1 week after |
| Zucchini | Set out | April 24 – June 14 | 1 week after |
| Cucumbers | Direct sow | May 1 – June 21 | 2 weeks after |
| Okra | Direct sow | May 1 – June 21 | 2 weeks after |
| Okra | Set out | May 1 – June 21 | 2 weeks after |
| Peppers | Set out | May 1 – June 21 | 2 weeks after |
| Southern Peas | Direct sow | May 1 – June 21 | 2 weeks after |
| Sweet Potato | Set out | May 1 – June 21 | 2 weeks after |
The week offsets are conventional extension guidance and vary by variety; the freeze dates they are counted from are measured. For a single date rather than a range, run when do I start my seeds? with your own ZIP code.
What survives the winter changes across Michigan
Of 74 perennial fruits, nuts, berries, vegetables and herbs, 58 come through the winter in zone 7a and only 34 in zone 4a. Winter hardiness runs on the zone alone, so each row below is exact for the ZIP codes in it.
| Zone | ZIPs | Survive | Fail for being too warm |
|---|---|---|---|
| 4a | 12 | 34 of 74 | 0 |
| 4b | 37 | 34 of 74 | 0 |
| 5a | 125 | 48 of 74 | 0 |
| 5b | 104 | 48 of 74 | 0 |
| 6a | 532 | 51 of 74 | 0 |
| 6b | 180 | 51 of 74 | 0 |
| 7a | 1 | 58 of 74 | 1 |
The last column is the counterintuitive one. Most temperate fruit needs a documented number of hours below about 45 °F to break dormancy and set a crop, so an apple fails in a winter that is too warm; currants and rhubarb cook in the summer heat that comes with it. See the full list with reasons.
Your own ZIP
Work out your own dates
Each of these takes a ZIP code and answers for that ZIP alone, citing the station it used and how far away it is. There is a ZIP box in the header of every page.
- What survives my winter?
Runs on the hardiness zone, so it answers exactly for your ZIP code rather than for Michigan as a whole — 74 perennial fruits, berries, vegetables and herbs.
- When do I start my seeds?
Dates every spring job from your own last freeze — sow indoors, set out, direct sow.
- When do I sow the next round?
How often each crop is worth re-sowing, and when the next sowing is due.
- What can I still plant?
Counts the growing days left before your first fall freeze, crop by crop.
Metro areas in Michigan
16 metro areas here have its own page, with the freeze dates from every station serving it, a spring calendar built from those stations, and every ZIP code in it listed with that ZIP code's exact zone and nearest station.
- Detroit-Warren-Dearborn, MI Zones 6a–6b
- Grand Rapids-Wyoming-Kentwood, MI Zones 5b–7a
- Lansing-East Lansing, MI Zone 6a
- Traverse City, MI Zones 5a–6b
- South Bend-Mishawaka, IN-MI Zone 6a
- Flint, MI Zone 6a
- Niles, MI Zones 6a–6b
- Jackson, MI Zone 6a
- Saginaw, MI Zone 6a
- Kalamazoo-Portage, MI Zone 6a
- Monroe, MI Zones 6a–6b
- Ann Arbor, MI Zone 6a
- Muskegon-Norton Shores, MI Zones 6a–6b
- Battle Creek, MI Zone 6a
- Bay City, MI Zones 5b–6a
- Midland, MI Zone 6a
Counties in Michigan
24 countys here have its own page, listing every ZIP code in it with that ZIP code's exact zone and nearest station. These are the smaller places outside the metro areas above — where most of Michigan's ZIP codes actually are.
- Houghton County, MI Zones 4b–5b
- Lenawee County, MI Zone 6a
- Sanilac County, MI Zone 6a
- Chippewa County, MI Zones 4b–5b
- Allegan County, MI Zones 6a–6b
- Van Buren County, MI Zones 6a–6b
- Huron County, MI Zone 6a
- Tuscola County, MI Zone 6a
- Marquette County, MI Zones 4a–5b
- Menominee County, MI Zones 5a–5b
- Shiawassee County, MI Zone 6a
- Antrim County, MI Zones 5a–6a
- Dickinson County, MI Zones 4b–5a
- Delta County, MI Zones 4b–5b
- Emmet County, MI Zones 4b–5b
- Mackinac County, MI Zones 5a–5b
- Alger County, MI Zones 5a–5b
- Oceana County, MI Zones 5b–6b
- Ontonagon County, MI Zones 4b–5a
- Newaygo County, MI Zones 5a–6a
- Baraga County, MI Zones 4a–5a
- Cheboygan County, MI Zones 4b–5a
- Charlevoix County, MI Zones 5a–6a
- Ogemaw County, MI Zone 5a
Other states to compare
Gear
If you want to act on this
Each link opens an Amazon search rather than a product we picked. We have not tested these and do not rank them — the search is the honest version, and you choose.
- Trunk wrapZone 4a is cold enough that winter sun on a young trunk does more damage than the cold does.
- Row cover and frost clothThe season here closes at the first fall freeze dated above — a cover buys back some of those days at the end.
- MulchFor the perennials nearest their cold limit in zone 4a, where an insulated crown is what decides whether they come back.
As an Amazon Associate we earn from qualifying purchases. That costs you nothing extra, and it buys no influence over anything on this site: the dates come from NOAA normals and the zones from the USDA, and no product affects either.
Sources
Where these numbers come from
The hardiness zone is the USDA 2023 Plant Hardiness Zone Map, published per ZIP code by PRISM at Oregon State. The freeze dates, growing seasons and summer highs are NOAA's 1991–2020 Climate Normals, read from every station in Michigan. Which ZIP codes are in Michigan comes from the Census ZIP-to-county relation, since a county's federal code begins with its state's. Nothing here is estimated.
This page names no single station for Michigan on purpose. Picking one to represent a state sounds reasonable and is not — the same reason the metro pages refuse it, only more so at this size. Instead every range names the station at each end, so you can check both without either one being made to speak for the state.