Frost dates for 48060Port Huron, MI
The average last spring frost in Port Huron is April 19 and the average first fall frost is November 3, giving a typical growing season of about 196 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 19
- Average first fall frost
- Nov 3
- Growing season
- 196 days
Safer after May 4 (1-in-10 risk)
Possible by Oct 20 (1-in-10 risk)
First frost typically in 1 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) | Apr 18 · May 1 · May 18 | Oct 6 · Oct 22 · Nov 4 | 172 days | 100% |
| Frost / freeze (32°F) | Apr 7 · Apr 19 · May 4 | Oct 20 · Nov 3 · Nov 16 | 196 days | 100% |
| Hard freeze (28°F) | Mar 25 · Apr 7 · Apr 21 | Nov 1 · Nov 12 · Nov 28 | 219 days | 100% |
Planting calendar for Port Huron
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 | Mar 19 – May 25 |
| Tomatoes | Transplant outdoors | May 5 – Jul 14 |
| Peppers | Start seeds indoors | Mar 19 – Apr 19 |
| Peppers | Transplant outdoors | May 19 – Jun 19 |
| Eggplant | Start seeds indoors | Apr 5 – May 4 |
| Eggplant | Transplant outdoors | May 19 – Jun 19 |
| Cucumbers | Sow outdoors | May 19 – Jul 24 |
| Summer squash | Sow outdoors | May 5 – Jun 19 |
| Winter squash & pumpkins | Sow outdoors | May 19 – Jun 19 |
| Snap beans | Sow outdoors | May 5 – Aug 16 |
| Sweet corn | Sow outdoors | May 5 – Jul 14 |
| Watermelon & cantaloupe | Sow outdoors | May 19 – Jun 19 |
| Okra | Sow outdoors | May 12 – Jun 4 |
| Peas | Sow outdoors (spring) | Mar 19 – May 4 |
| Potatoes | Plant outdoors (spring) | Mar 19 – May 19 |
| Onions | Start seeds indoors (spring) | Feb 5 – Mar 4 |
| Onions | Transplant outdoors (spring) | Apr 5 – May 4 |
| Broccoli | Start seeds indoors (spring) | Mar 1 – Apr 4 |
| Broccoli | Transplant outdoors (spring) | Apr 5 – May 4 |
| Broccoli | Start seeds indoors (fall) | Jul 4 – Jul 14 |
| Broccoli | Transplant outdoors (fall) | Aug 3 – Aug 14 |
| Cabbage | Start seeds indoors (spring) | Feb 19 – Mar 19 |
| Cabbage | Transplant outdoors (spring) | Mar 19 – Apr 19 |
| Cabbage | Start seeds indoors (fall) | Jun 24 – Jul 24 |
| Cabbage | Transplant outdoors (fall) | Jul 24 – Aug 24 |
| Leaf lettuce | Sow outdoors (spring) | Mar 19 – Jun 4 |
| Leaf lettuce | Sow outdoors (fall) | Jul 24 – Sep 9 |
| Spinach | Sow outdoors (spring) | Mar 12 – Apr 25 |
| Spinach | Sow outdoors (fall) | Aug 10 – Sep 14 |
| Radishes | Sow outdoors (spring) | Mar 19 – May 9 |
| Radishes | Sow outdoors (fall) | Jul 24 – Sep 24 |
| Kale | Sow outdoors (spring) | Apr 5 – Apr 25 |
| Kale | Sow outdoors (fall) | Jul 17 – Aug 24 |
| Carrots | Sow outdoors (spring) | Apr 19 – Jun 4 |
| Carrots | Sow outdoors (fall) | Jun 24 – Aug 9 |
| Garlic | Plant outdoors (fall) | Oct 24 – Nov 24 |
Where these dates come from
ZIP code 48060 is matched to the NOAA station Port Huron, MI, 4 km away, at 590 ft elevation (20 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Port Huron, MI (used) | 590 ft | Apr 19 | Nov 3 |
| Richmond 4 Nnw, MI | 765 ft | May 1 | Oct 20 |
| Lexington Wtp, MI | 622 ft | May 4 | Oct 24 |
| Yale 1 Nnw, MI | 820 ft | May 12 | Oct 5 |
Frost dates near Port Huron
- Port Huron, MI 48061 · last Apr 19, first Nov 3
- Marysville, MI 48040 · last Apr 19, first Nov 3
- North Street, MI 48049 · last Apr 19, first Nov 3
- Fort Gratiot, MI 48059 · last Apr 19, first Nov 3
- Smiths Creek, MI 48074 · last Apr 19, first Nov 3
- Jeddo, MI 48032 · last May 4, first Oct 24
- Saint Clair, MI 48079 · last Apr 19, first Nov 3
- Goodells, MI 48027 · last May 1, first Oct 20
Frequently asked questions
- When is the last frost in Port Huron, MI?
- For ZIP code 48060, the average last spring frost (32°F) is April 19, based on NOAA 1991-2020 climate normals for the Port Huron, MI weather station. There is a 1-in-10 chance of a frost after May 4.
- When is the first frost in Port Huron, MI?
- The average first fall frost (32°F) is November 3. There is a 1-in-10 chance of frost by October 20, so tender plants are at risk from that point on.
- How long is the growing season in 48060?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 196 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.