Frost dates for 48603Saginaw, MI
The average last spring frost in Saginaw is April 29 and the average first fall frost is October 21, giving a typical growing season of about 175 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 29
- Average first fall frost
- Oct 21
- Growing season
- 175 days
Safer after May 13 (1-in-10 risk)
Possible by Oct 5 (1-in-10 risk)
Last frost typically in 178 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 26 · May 7 · May 23 | Sep 27 · Oct 9 · Oct 22 | 153 days | 100% |
| Frost / freeze (32°F) | Apr 14 · Apr 29 · May 13 | Oct 5 · Oct 21 · Nov 2 | 175 days | 100% |
| Hard freeze (28°F) | Apr 2 · Apr 17 · May 1 | Oct 20 · Nov 3 · Nov 16 | 200 days | 100% |
Planting calendar for Saginaw
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 29 – Jun 4 |
| Tomatoes | Transplant outdoors | May 15 – Jul 1 |
| Peppers | Start seeds indoors | Mar 29 – Apr 29 |
| Peppers | Transplant outdoors | May 29 – Jun 29 |
| Eggplant | Start seeds indoors | Apr 15 – May 14 |
| Eggplant | Transplant outdoors | May 29 – Jun 29 |
| Cucumbers | Sow outdoors | May 29 – Jul 11 |
| Summer squash | Sow outdoors | May 15 – Jun 29 |
| Winter squash & pumpkins | Sow outdoors | May 29 – Jun 29 |
| Snap beans | Sow outdoors | May 15 – Aug 3 |
| Sweet corn | Sow outdoors | May 15 – Jul 1 |
| Watermelon & cantaloupe | Sow outdoors | May 29 – Jun 29 |
| Okra | Sow outdoors | May 22 – Jun 14 |
| Peas | Sow outdoors (spring) | Mar 29 – May 14 |
| Potatoes | Plant outdoors (spring) | Mar 29 – May 29 |
| Onions | Start seeds indoors (spring) | Feb 15 – Mar 14 |
| Onions | Transplant outdoors (spring) | Apr 15 – May 14 |
| Broccoli | Start seeds indoors (spring) | Mar 11 – Apr 14 |
| Broccoli | Transplant outdoors (spring) | Apr 15 – May 14 |
| Broccoli | Start seeds indoors (fall) | Jun 21 – Jul 1 |
| Broccoli | Transplant outdoors (fall) | Jul 21 – Aug 1 |
| Cabbage | Start seeds indoors (spring) | Mar 1 – Mar 29 |
| Cabbage | Transplant outdoors (spring) | Mar 29 – Apr 29 |
| Cabbage | Start seeds indoors (fall) | Jun 11 – Jul 11 |
| Cabbage | Transplant outdoors (fall) | Jul 11 – Aug 11 |
| Leaf lettuce | Sow outdoors (spring) | Mar 29 – Jun 14 |
| Leaf lettuce | Sow outdoors (fall) | Jul 11 – Aug 27 |
| Spinach | Sow outdoors (spring) | Mar 22 – May 5 |
| Spinach | Sow outdoors (fall) | Jul 28 – Sep 1 |
| Radishes | Sow outdoors (spring) | Mar 29 – May 19 |
| Radishes | Sow outdoors (fall) | Jul 11 – Sep 11 |
| Kale | Sow outdoors (spring) | Apr 15 – May 5 |
| Kale | Sow outdoors (fall) | Jul 4 – Aug 11 |
| Carrots | Sow outdoors (spring) | Apr 29 – Jun 14 |
| Carrots | Sow outdoors (fall) | Jun 11 – Jul 27 |
| Garlic | Plant outdoors (fall) | Oct 11 – Nov 11 |
Where these dates come from
ZIP code 48603 is matched to the NOAA station Saginaw #3, MI, 8.2 km away, at 600 ft elevation (33 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Saginaw #3, MI (used) | 600 ft | Apr 29 | Oct 21 |
| Saginaw Mbs Intl Ap, MI | 660 ft | Apr 26 | Oct 17 |
| Auburn 2Ne, MI | 605 ft | May 3 | Oct 14 |
| Midland, MI | 640 ft | Apr 29 | Oct 16 |
Frost dates near Saginaw
- Saginaw, MI 48605 · last Apr 29, first Oct 21
- Carrollton, MI 48724 · last Apr 29, first Oct 21
- University Center, MI 48710 · last May 3, first Oct 14
- Freeland, MI 48623 · last Apr 26, first Oct 17
- Hemlock, MI 48626 · last Apr 26, first Oct 17
- Auburn, MI 48611 · last May 3, first Oct 14
- Bay City, MI 48706 · last May 3, first Oct 14
- Bridgeport, MI 48722 · last Apr 29, first Oct 21
Frequently asked questions
- When is the last frost in Saginaw, MI?
- For ZIP code 48603, the average last spring frost (32°F) is April 29, based on NOAA 1991-2020 climate normals for the Saginaw #3, MI weather station. There is a 1-in-10 chance of a frost after May 13.
- When is the first frost in Saginaw, MI?
- The average first fall frost (32°F) is October 21. There is a 1-in-10 chance of frost by October 5, so tender plants are at risk from that point on.
- How long is the growing season in 48603?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 175 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.