Frost Dates for Royal Oak, MI
In Royal Oak, MI, the average last spring frost is around Apr 21 and the average first fall frost around Oct 31, for a growing season of about 190 days. For frost-tender plants, wait until May 6, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the Detroit City Airport, MI weather station, 10 miles away, elevation 626 ft. Frost can come earlier in low spots and valleys and later near cities and large lakes.
Frost probability by date
Chance of a 32°F frost after the spring date, or before the fall date.
| Chance | Last spring frost | First fall frost |
|---|---|---|
| 10% | May 6 | Oct 17 |
| 20% | May 1 | Oct 21 |
| 30% | Apr 27 | Oct 24 |
| 40% | Apr 23 | Oct 28 |
| 50% | Apr 21 | Oct 31 |
| 60% | Apr 18 | Nov 1 |
| 70% | Apr 16 | Nov 3 |
| 80% | Apr 12 | Nov 6 |
| 90% | Apr 7 | Nov 11 |
Light frost vs. hard freeze
Average (50%) dates for each temperature. Tender plants are damaged at 36°F; most hardy crops survive until 28°F.
| Temperature | Last in spring | First in fall |
|---|---|---|
| Light frost (36°F) | May 1 | Oct 18 |
| Frost / freeze (32°F) | Apr 21 | Oct 31 |
| Hard freeze (28°F) | Apr 8 | Nov 9 |
Planting calendar for Royal Oak
Transplant Apr 28 – May 12
Transplant May 5 – May 19
Transplant May 5 – May 19
Transplant Apr 28 – May 12
Sow or transplant Apr 28 – May 12
Sow or transplant Apr 28 – May 12
Sow or transplant May 5 – May 19
Sow or transplant Mar 24 – Apr 7
Fall sowing Sep 5 – Oct 3
Fall sowing Sep 5 – Sep 26
Fall sowing Aug 22 – Sep 5
Sow or transplant Mar 24 – Apr 7
Fall sowing Aug 22 – Sep 19
Transplant Apr 7 – Apr 21
Fall sowing Aug 8 – Aug 22
Transplant Mar 31 – Apr 14
Fall sowing Aug 8 – Aug 22
Fall sowing Aug 8 – Aug 22
Fall sowing Sep 19 – Oct 10
Fall sowing Aug 22 – Sep 5
Plant Mar 24 – Apr 7
Based on the average last frost (Apr 21) and first frost (Oct 31). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.