USDA zone 5b in Michigan
USDA plant hardiness zone 5b covers 40 locations across Michigan (average annual extreme minimum −15 to −10 °F): Alpena, MI, Baldwin, MI, Big Bay, MI, Big Rapids, MI, Boyne, MI, Brethren, MI, and 34 more. Average last spring frost across this group ranges April 30 (Weidman) to May 30 (Chatham), and growing seasons run 119–171 days (Brethren to Weidman) — even within one state, because hardiness sets winter survival, not planting dates. The table below gives every Michigan location's own frost dates; the printable planting calendar uses East Tawas, this group's median-season location.
- USDA zone
- 5b−15 to −10 °F
- Last frost range
- Apr 30–May 30avg, 32°F
- First frost range
- Sep 24–Oct 23avg, 32°F
- Growing season range
- 119–171days
Locations in this group
Every location below shares this zone and a nearby weather station, but keeps its own frost dates — find your town for its own numbers, or use the ZIP planner on the home page for an instant personalized answer.
| Location | Also covers | Nearest station | Last frost | First frost | Season (days) |
|---|---|---|---|---|---|
| Alpena | — | Alpena Wwtp | May 5 | Oct 17 | 163 |
| Baldwin | — | Manistee 3se | May 14 | Oct 12 | 151 |
| Big Bay | — | Big Bay 1nw | May 22 | Oct 6 | 137 |
| Big Rapids | Newaygo, Lake Isabella, Howard, White Cloud, Baldwin, Mecosta, +3 more | Big Rapids Wtp | May 13 | Oct 2 | 142 |
| Boyne | Alba | Boyne Falls | May 23 | Oct 3 | 133 |
| Brethren | Wellston | Wellston 1n | May 28 | Sep 25 | 119 |
| Buckley | Kingsley | Traverse City Cherry Cptl Ap | May 12 | Oct 16 | 155 |
| Carp Lake | Harbor Springs | Cross Village 1e | May 15 | Oct 16 | 152 |
| Chatham | — | Chatham Exp Farm 2 | May 30 | Sep 27 | 119 |
| Cheboygan | — | Cheboygan | May 11 | Oct 11 | 152 |
| Clare | Gladwin, Farwell | Gladwin | May 9 | Oct 4 | 148 |
| Copemish | — | Beulah 7ssw | May 7 | Oct 20 | 163 |
| De Tour | — | Detour Village | May 5 | Oct 20 | 167 |
| Dollar Bay | Hancock, Hubbell, Atlantic Mine, Lake Linden, Dodgeville, Fulton, +2 more | Hancock Houghton Co Ap | May 17 | Oct 1 | 138 |
| Eagle Harbor | — | Copper Harbor | May 10 | Oct 21 | 161 |
| East Jordan | Bellaire, Central Lake, Ellsworth | E Jordan | May 23 | Oct 2 | 131 |
| East Tawas * | Au Sable, Tawas | E Tawas | May 8 | Oct 5 | 148 |
| Edmore | — | Alma | May 1 | Oct 13 | 164 |
| Fremont | — | Fremont 4 Wsw | May 8 | Oct 11 | 155 |
| Garden | — | Manistique Wwtp | May 9 | Oct 10 | 154 |
| Garden | — | Garden Corners | May 16 | Sep 24 | 129 |
| Grand Marais | — | Grand Marais 2 E | May 27 | Oct 10 | 138 |
| Hubbard Lake | Lincoln | Harrisville 2nne | May 8 | Oct 16 | 160 |
| Mackinac Island | Mackinaw | St Ignace Mackinac Br | May 7 | Oct 23 | 167 |
| Manton | Mesick, Caberfae | Cadillac | May 19 | Oct 1 | 135 |
| Menominee | Peshtigo | Marinette | May 4 | Oct 11 | 160 |
| Millersburg | — | Onaway 4n | May 22 | Oct 2 | 135 |
| Munising | — | Munising | May 16 | Oct 14 | 148 |
| Naubinway | — | Engadine Mdot | May 26 | Sep 30 | 127 |
| Posen | — | Alpena Co Rgnl Ap | May 17 | Oct 1 | 136 |
| Sand Lake | — | Hale Loud Dam | May 16 | Oct 5 | 143 |
| Skidway Lake | — | W Branch 3se | May 15 | Oct 4 | 143 |
| South Boardman | Alden | Kalkaska | May 24 | Oct 1 | 128 |
| St. Ignace | — | Moran | May 23 | Sep 30 | 130 |
| Standish | Omer, Turner, Sterling, Twining | Standish 4ne | May 5 | Oct 10 | 156 |
| Stanton | Lakeview, Sheridan, Trufant, McBride, Pierson | Greenville 2 Nne | May 18 | Sep 28 | 133 |
| Trowbridge Park | — | Marquette | May 8 | Oct 21 | 164 |
| Walkerville | Hesperia | Hesperia 4 Wnw | May 17 | Oct 1 | 137 |
| Walloon Lake | Conway, Bay View | Petoskey | May 6 | Oct 20 | 166 |
| Weidman | Winn | Central Michigan Univ | Apr 30 | Oct 20 | 171 |
* East Tawas is this group's median-season location — the calendar below is computed from its data.
Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.
Planting calendar (East Tawas, representative)
Computed from East Tawas's average frost dates — the median-season location in this Michiganzone 5b group. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees — your own location's dates may run a week or two earlier or later (see the table above).
- Start indoors
- Plant out
- Fall sowing
- First harvest
| Crop | Frost tolerance | Start indoors | Plant out | First harvest | Fall planting | Season fit |
|---|---|---|---|---|---|---|
| Tomato | Tender | Mar 13 – Mar 27 | May 15 – May 22 | Jul 14 – Aug 3 | — | matures comfortably |
| Pepper | Very tender | Feb 27 – Mar 13 | May 22 – May 29 | Jul 21 – Aug 20 | — | matures comfortably |
| Cucumber | Tender | Apr 10 – Apr 17 | May 15 – May 22 | Jul 4 – Jul 24 | — | matures comfortably |
| Summer squash / zucchini | Tender | — | May 15 – May 22 | Jun 29 – Jul 14 | — | matures comfortably |
| Bush bean | Tender | — | May 15 – May 22 | Jul 4 – Jul 14 | Aug 6 – Aug 16 | matures comfortably |
| Sweet corn | Tender | — | May 8 – May 22 | Jul 7 – Aug 6 | — | matures comfortably |
| Basil | Very tender | Mar 27 – Apr 10 | May 15 – May 22 | Jun 14 – Jun 29 | — | matures comfortably |
| Lettuce | Half-hardy | Mar 27 – Apr 10 | Apr 10 – Apr 24 | May 25 – Jun 9 | Jul 23 – Aug 7 | matures comfortably |
| Pea | Hardy | — | Mar 27 – Apr 10 | May 21 – Jun 5 | Jul 13 – Jul 28 | matures comfortably |
| Spinach | Hardy | — | Mar 27 – Apr 10 | May 6 – May 16 | Aug 2 – Aug 12 | matures comfortably |
| Carrot | Half-hardy | — | Apr 17 – Apr 24 | Jun 16 – Jul 6 | Jul 3 – Jul 23 | matures comfortably |
| Broccoli | Half-hardy | Mar 13 – Mar 27 | Apr 10 – Apr 24 | Jun 4 – Jun 24 | Jul 8 – Jul 28 | matures comfortably |
Which crops fit this growing season
Using East Tawas's own 148-day growing season (32°F, NOAA 1991–2020 median) against each crop's real days-to-maturity range: 12 of 12 crops mature here with comfortable margin. A different location in the table above with a longer or shorter season will get a different mix — the ZIP planner on the home page gives your own.
Frost & freeze dates (East Tawas)
From NOAA's 1991–2020 Climate Normals at station USC00202423. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 — the conservative date to plant after or harvest before.
| Threshold | Last spring — avg | Last spring — 90%-safe | First fall — avg | First fall — 90%-safe | Season (days) |
|---|---|---|---|---|---|
| 36°F | May 23 | Jun 6 | Sep 26 | Oct 7 | 125 |
| 32°F (freeze) | May 8 | May 26 | Oct 5 | Oct 17 | 148 |
| 28°F | Apr 28 | May 13 | Oct 17 | Nov 1 | 171 |
| 24°F | Apr 16 | Apr 29 | Nov 1 | Nov 15 | 198 |
Growing degree days
Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. This group's median GDD (base 50°F) across all 40 locations is 2,044; East Tawas's own reading is shown below.
| Model | °F·days | Used for |
|---|---|---|
| Base 50°F (warm-season) | 2,192 | standard warm-season base (tomato, corn, beans) |
| Base 40°F (cool-season) | 4,059 | cool-season crops (brassicas, greens) |
Hardiness zone 5b in Michigan
Zone 5b means an average annual extreme minimum winter temperature of about −15 to −10 °F on the USDA's 2023 map — the number that tells you which perennials, shrubs, and trees reliably survive an average winter here. It does not set your planting dates, which come from the frost calendar above. Michigan spans 7 hardiness zones in this dataset — see all Michigan locations for the full range, including zones4a, 4b, 5a, 6a, 6b, 7a.
Explore zone 5b in other states at zone 5b, or see all USDA hardiness zones.
Frequently asked questions
- What does USDA hardiness zone 5b mean in Michigan?
- Zone 5b means an average annual extreme minimum winter temperature of −15 to −10 °F — the standard USDA measure of which perennials survive winter. 40 locations in Michigan fall in this zone. It does not set planting dates; see the frost calendar below for that.
- Where in Michigan's zone 5b is the growing season longest?
- Weidman runs the longest season on this page at about 171 days; Brethren is shortest at about 119 days — they share the same hardiness zone, but they sit at different weather stations, so their frost calendars differ.
- When should I plant tomatoes in Michigan's zone 5b?
- Using East Tawas's frost dates (this page's median-season location): start seeds indoors about Mar 13 – Mar 27, then transplant outside about May 15 – May 22. Your own location in the table above may differ by a week or two — use the ZIP planner on the home page for your exact station's dates.
- Does every location in Michigan's zone 5b have the same frost dates?
- No — they do not all share a weather station, so frost dates vary by a week or more across the 40 locations listed (see the table above for each location's own dates).
Sources & method
Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020, one reading per location's own nearest station (see the table above). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to each location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.