Detroit, MI · zone 6b · ~184 frost-free days
When to plant in Detroit: frost dates and zone 6b.
In Detroit, the typical last spring frost lands around Apr 25 and the first fall frost around Oct 26, giving you about 184 frost-free days. Cool-season crops go out before the last frost; warm-season crops wait until after it.
The 2026 windows
Sow dates for Detroit, keyed to your frost.
| Crop | Start indoors | Spring sow / set out | Fall sow |
|---|---|---|---|
| Tomato, slicing | Mar 21 to May 21 | May 2 to Jul 2 | — |
| Lettuce, leaf | — | Mar 18 to May 2 | Aug 12 to Oct 11 |
| Carrot | — | Mar 18 to Apr 20 | Jul 31 to Aug 26 |
| Bush Bean | — | Apr 25 to Jun 15 | Jul 12 to Aug 14 |
| Cucumber, slicing | — | May 2 to Aug 1 | — |
| Pepper, bell | Mar 30 to May 21 | May 11 to Jul 2 | — |
| Kale | Feb 4 to Mar 4 | Mar 18 to Apr 15 | Jul 26 to Sep 10 |
| Spinach | — | Mar 4 to Apr 15 | Aug 12 to Sep 30 |
Detroit sits in Zone 6b, but two gardens in the same city can be a week or two apart. The planner works from your ZIP code's frost dates, not the zone, so the dates land right for your block, not the metro average.
Build your Detroit garden plan.
Tell the free planner what you want to eat and who you're feeding. It returns plant counts, spacing, and frost-safe sow dates for ZIP 48226 in about 60 seconds.
Detroit planting questions
What planting zone is Detroit, MI?+
Detroit is in USDA hardiness zone 6b. Growing zone, gardening zone, and planting zone all mean the same thing: the USDA number, 6b here. It tells you what survives winter, not when to plant. Frost dates set your planting time, and the free planner uses your exact ZIP code's frost dates, which can differ by weeks across one metro.
When is the last frost date in Detroit?+
The typical last spring frost in Detroit, MI is around Apr 25. That is an average from local history, not a guarantee, so tender crops like tomatoes and peppers are safer with a week of buffer after it.
When is the first frost date in Detroit?+
The typical first fall frost in Detroit, MI arrives around Oct 26, closing a growing season of roughly 184 frost-free days. Count backward from it to find the last date a fall crop can still finish.
What can I plant now in Detroit?+
It depends on the date. Cool-season crops like lettuce, kale, and spinach go out weeks before the last frost; warm-season crops like tomatoes and peppers wait until after Apr 25. The table above shows each crop's window; the free planner turns your ZIP into an exact, dated calendar.