Frost dates for 49783Sault Sainte Marie, MI
The average last spring frost in Sault Sainte Marie is May 22 and the average first fall frost is October 4, giving a typical growing season of about 136 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 22
- Average first fall frost
- Oct 4
- Growing season
- 136 days
Safer after Jun 4 (1-in-10 risk)
Possible by Sep 22 (1-in-10 risk)
Last frost typically in 208 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | May 22 · Jun 2 · Jun 18 | Sep 8 · Sep 25 · Oct 5 | 112 days | 100% |
| Frost / freeze (32°F) | May 5 · May 22 · Jun 4 | Sep 22 · Oct 4 · Oct 18 | 136 days | 100% |
| Hard freeze (28°F) | Apr 24 · May 7 · May 22 | Oct 3 · Oct 17 · Nov 1 | 164 days | 100% |
Planting calendar for Sault Sainte Marie
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Apr 21 – Jun 27 |
| Tomatoes | Transplant outdoors | Jun 7 – Jun 14 |
| Peppers | Start seeds indoors | Apr 21 – May 22 |
| Peppers | Transplant outdoors | Jun 21 – Jul 22 |
| Eggplant | Start seeds indoors | May 8 – Jun 6 |
| Eggplant | Transplant outdoors | Jun 21 – Jul 22 |
| Cucumbers | Sow outdoors | Jun 21 – Jun 24 |
| Summer squash | Sow outdoors | Jun 7 – Jul 22 |
| Winter squash & pumpkins | Sow outdoors | Jun 21 – Jul 22 |
| Snap beans | Sow outdoors | Jun 7 – Jul 17 |
| Sweet corn | Sow outdoors | Jun 7 – Jun 14 |
| Watermelon & cantaloupe | Sow outdoors | Jun 21 – Jul 22 |
| Okra | Sow outdoors | Jun 14 – Jul 7 |
| Peas | Sow outdoors (spring) | Apr 21 – Jun 6 |
| Potatoes | Plant outdoors (spring) | Apr 21 – Jun 21 |
| Onions | Start seeds indoors (spring) | Mar 10 – Apr 6 |
| Onions | Transplant outdoors (spring) | May 8 – Jun 6 |
| Broccoli | Start seeds indoors (spring) | Apr 3 – May 7 |
| Broccoli | Transplant outdoors (spring) | May 8 – Jun 6 |
| Broccoli | Start seeds indoors (fall) | Jun 4 – Jun 14 |
| Broccoli | Transplant outdoors (fall) | Jul 4 – Jul 15 |
| Cabbage | Start seeds indoors (spring) | Mar 24 – Apr 21 |
| Cabbage | Transplant outdoors (spring) | Apr 21 – May 22 |
| Cabbage | Start seeds indoors (fall) | May 25 – Jun 24 |
| Cabbage | Transplant outdoors (fall) | Jun 24 – Jul 25 |
| Leaf lettuce | Sow outdoors (spring) | Apr 21 – Jul 7 |
| Leaf lettuce | Sow outdoors (fall) | Jun 24 – Aug 10 |
| Spinach | Sow outdoors (spring) | Apr 14 – May 28 |
| Spinach | Sow outdoors (fall) | Jul 11 – Aug 15 |
| Radishes | Sow outdoors (spring) | Apr 21 – Jun 11 |
| Radishes | Sow outdoors (fall) | Jun 24 – Aug 25 |
| Kale | Sow outdoors (spring) | May 8 – May 28 |
| Kale | Sow outdoors (fall) | Jun 17 – Jul 25 |
| Carrots | Sow outdoors (spring) | May 22 – Jul 7 |
| Carrots | Sow outdoors (fall) | May 25 – Jul 10 |
| Garlic | Plant outdoors (fall) | Sep 24 – Oct 25 |
Where these dates come from
ZIP code 49783 is matched to the NOAA station Sault Ste Marie, MI, 12.4 km away, at 630 ft elevation (7 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Sault Ste Marie, MI (used) | 630 ft | May 22 | Oct 4 |
| Sault Ste Marie Sanderson Fld, MI | 722 ft | May 9 | Oct 11 |
| Pickford 3Ne, MI | 629 ft | May 31 | Sep 25 |
| Rudyard 4N, MI | 753 ft | May 24 | Oct 1 |
Frost dates near Sault Sainte Marie
- Kincheloe, MI 49784 · last May 9, first Oct 11
- Dafter, MI 49724 · last May 9, first Oct 11
- Barbeau, MI 49710 · last May 31, first Sep 25
- Kinross, MI 49752 · last May 24, first Oct 1
- Pickford, MI 49774 · last May 31, first Sep 25
- Brimley, MI 49715 · last May 24, first Oct 1
- Goetzville, MI 49736 · last May 31, first Sep 25
- Rudyard, MI 49780 · last May 21, first Oct 1
Frequently asked questions
- When is the last frost in Sault Sainte Marie, MI?
- For ZIP code 49783, the average last spring frost (32°F) is May 22, based on NOAA 1991-2020 climate normals for the Sault Ste Marie, MI weather station. There is a 1-in-10 chance of a frost after June 4.
- When is the first frost in Sault Sainte Marie, MI?
- The average first fall frost (32°F) is October 4. There is a 1-in-10 chance of frost by September 22, so tender plants are at risk from that point on.
- How long is the growing season in 49783?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 136 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.