Detroit, Michigan: planting zone & frost dates
Detroit is in USDA plant hardiness zone 6b, where the average coldest winter night reaches -5 to 0°F (-20.6 to -17.8°C). The typical last spring frost is around May 2 and the first fall frost around Oct 20.
Frost dates
| Probability | Last spring frost (32°F) | First fall frost (32°F) |
|---|---|---|
| Safer (10% risk) | May 11 | Oct 10 |
| Typical planning date (30% risk) | May 2 | Oct 20 |
| Median (50%) | Apr 27 | Oct 25 |
How to read this: after the spring "10% risk" date, a 32°F frost happens in only about 1 year in 10. In fall, the "10% risk" date is the early end — a frost before it happens about 1 year in 10.
Frost data comes from NOAA station DEARBORN #2, MI (USC00202016), 4.4 mi (7.1 km) from the city center and 33 ft lower than the city center (-10 m). Record used for the 1991–2020 normals: 14 years.
Hardiness zone across Detroit
All 30 ZIP codes covering Detroit are in zone 6b.
ZIP codes in Detroit and their zones
| ZIP | Zone | Share of city land |
|---|---|---|
| 48228 | 6b | 6.4% |
| 48219 | 6b | 6.1% |
| 48234 | 6b | 5.6% |
| 48227 | 6b | 5.4% |
| 48209 | 6b | 4.9% |
| 48213 | 6b | 4.7% |
| 48205 | 6b | 4.6% |
| 48207 | 6b | 4.5% |
| 48235 | 6b | 4.5% |
| 48223 | 6b | 4.4% |
| 48224 | 6b | 4.2% |
| 48238 | 6b | 3.9% |
| 48203 | 6b | 3.8% |
| 48221 | 6b | 3.7% |
| 48204 | 6b | 3.6% |
| 48210 | 6b | 3.6% |
| 48214 | 6b | 3.6% |
| 48211 | 6b | 2.8% |
| 48215 | 6b | 2.8% |
| 48212 | 6b | 2.6% |
| 48202 | 6b | 2.4% |
| 48208 | 6b | 2.3% |
| 48206 | 6b | 2.2% |
| 48217 | 6b | 1.7% |
| 48216 | 6b | 1.6% |
| 48201 | 6b | 1.4% |
| 48239 | 6b | 1.4% |
| 48226 | 6b | 0.9% |
| 48233 | 6b | 0.0% |
| 48243 | 6b | 0.0% |
Vegetable planting calendar for Detroit
Dates are counted from the 30%-risk frost dates above (last frost May 2, first frost Oct 20). Shift a week later in cold spots or low-lying ground.
| Crop | Start indoors | Transplant / plant out | Direct sow | Fall crop sow/plant |
|---|---|---|---|---|
| Tomato | Mar 7 – Mar 21 | May 9 – May 23 | — | — |
| Pepper | Feb 21 – Mar 7 | May 16 – May 30 | — | — |
| Lettuce | Mar 21 – Apr 4 | Apr 18 – May 9 | Apr 4 – May 16 | Aug 11 – Sep 8 |
| Green Beans | — | — | May 9 – Jun 13 | Jul 28 – Aug 11 |
| Sweet Corn | — | — | May 9 – Jun 6 | — |
| Zucchini & Summer Squash | Apr 4 – Apr 11 | May 9 – May 23 | May 9 – May 30 | Jul 28 – Aug 11 |
| Cucumber | Apr 4 – Apr 11 | May 16 – May 23 | May 9 – May 30 | Jul 28 – Aug 11 |
| Carrot | — | — | Apr 11 – May 16 | Jul 28 – Aug 11 |
| Onion | Feb 7 – Feb 21 | Apr 4 – Apr 18 | — | — |
| Potato | — | Apr 4 – Apr 25 | — | — |
| Basil | Mar 21 – Apr 4 | May 16 – May 30 | May 16 – Jun 6 | — |
| Spinach | — | — | Mar 21 – Apr 18 | Aug 25 – Sep 22 |
| Kale | Mar 7 – Mar 21 | Apr 4 – Apr 25 | Apr 4 – Apr 25 | Aug 11 – Sep 8 |
| Broccoli | Mar 7 – Mar 21 | Apr 18 – May 9 | — | Jul 28 – Aug 11 |
| Peas | — | — | Mar 21 – Apr 11 | Aug 11 – Aug 25 |
| Eggplant | Feb 21 – Mar 7 | May 16 – May 30 | — | — |
| Cabbage | Mar 7 – Mar 21 | Apr 4 – Apr 18 | — | Jul 28 – Aug 11 |
| Radish | — | — | Mar 28 – May 16 | Sep 8 – Oct 6 |
| Strawberry | — | Apr 4 – Apr 25 | — | — |
| Beets | — | — | Apr 11 – May 23 | Aug 11 – Aug 25 |
Nearby cities in Michigan
- Dearborn — zone 6b, last frost May 8, first frost Oct 9
- Warren — zone 6b, last frost Apr 27, first frost Oct 24
- Southfield — zone 6b, last frost May 8, first frost Oct 10
- Troy — zone 6b, last frost May 2, first frost Oct 16
- Sterling Heights — zone 6b, last frost May 5, first frost Oct 18
- Livonia — zone 6b, last frost May 8, first frost Oct 10
More: all Michigan cities · other zone 6b cities: Columbus, OH, Indianapolis, IN, Boston, MA, Kansas City, MO, Cincinnati, OH, Pittsburgh, PA, Buffalo, NY, Toledo, OH