Frost dates for 48761South Branch, MI
The average last spring frost in South Branch is May 21 and the average first fall frost is September 29, giving a typical growing season of about 129 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 21
- Average first fall frost
- Sep 29
- Growing season
- 129 days
Safer after Jun 5 (1-in-10 risk)
Possible by Sep 15 (1-in-10 risk)
Last frost typically in 200 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 20 · Jun 3 · Jun 23 | Sep 1 · Sep 16 · Sep 30 | 104 days | 100% |
| Frost / freeze (32°F) | May 5 · May 21 · Jun 5 | Sep 15 · Sep 29 · Oct 11 | 129 days | 100% |
| Hard freeze (28°F) | Apr 24 · May 7 · May 23 | Sep 27 · Oct 10 · Oct 26 | 155 days | 100% |
Planting calendar for South Branch
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 20 – Jun 26 |
| Tomatoes | Transplant outdoors | Jun 6 – Jun 9 |
| Peppers | Start seeds indoors | Apr 20 – May 21 |
| Peppers | Transplant outdoors | Jun 20 – Jul 21 |
| Eggplant | Start seeds indoors | May 7 – Jun 5 |
| Eggplant | Transplant outdoors | Jun 20 – Jul 21 |
| Cucumbers | Sow outdoors | Jun 20 – Jun 19 |
| Summer squash | Sow outdoors | Jun 6 – Jul 21 |
| Winter squash & pumpkins | Sow outdoors | Jun 20 – Jul 21 |
| Snap beans | Sow outdoors | Jun 6 – Jul 12 |
| Sweet corn | Sow outdoors | Jun 6 – Jun 9 |
| Watermelon & cantaloupe | Sow outdoors | Jun 20 – Jul 21 |
| Okra | Sow outdoors | Jun 13 – Jul 6 |
| Peas | Sow outdoors (spring) | Apr 20 – Jun 5 |
| Potatoes | Plant outdoors (spring) | Apr 20 – Jun 20 |
| Onions | Start seeds indoors (spring) | Mar 9 – Apr 5 |
| Onions | Transplant outdoors (spring) | May 7 – Jun 5 |
| Broccoli | Start seeds indoors (spring) | Apr 2 – May 6 |
| Broccoli | Transplant outdoors (spring) | May 7 – Jun 5 |
| Broccoli | Start seeds indoors (fall) | May 30 – Jun 9 |
| Broccoli | Transplant outdoors (fall) | Jun 29 – Jul 10 |
| Cabbage | Start seeds indoors (spring) | Mar 23 – Apr 20 |
| Cabbage | Transplant outdoors (spring) | Apr 20 – May 21 |
| Cabbage | Start seeds indoors (fall) | May 20 – Jun 19 |
| Cabbage | Transplant outdoors (fall) | Jun 19 – Jul 20 |
| Leaf lettuce | Sow outdoors (spring) | Apr 20 – Jul 6 |
| Leaf lettuce | Sow outdoors (fall) | Jun 19 – Aug 5 |
| Spinach | Sow outdoors (spring) | Apr 13 – May 27 |
| Spinach | Sow outdoors (fall) | Jul 6 – Aug 10 |
| Radishes | Sow outdoors (spring) | Apr 20 – Jun 10 |
| Radishes | Sow outdoors (fall) | Jun 19 – Aug 20 |
| Kale | Sow outdoors (spring) | May 7 – May 27 |
| Kale | Sow outdoors (fall) | Jun 12 – Jul 20 |
| Carrots | Sow outdoors (spring) | May 21 – Jul 6 |
| Carrots | Sow outdoors (fall) | May 20 – Jul 5 |
| Garlic | Plant outdoors (fall) | Sep 19 – Oct 20 |
Where these dates come from
ZIP code 48761 is matched to the NOAA station Lupton 1S, MI, 15.3 km away, at 908 ft elevation (30 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Lupton 1S, MI (used) | 908 ft | May 21 | Sep 29 |
| Hale Loud Dam, MI | 728 ft | May 16 | Oct 5 |
| Glennie 2Se, MI | 894 ft | May 19 | Sep 29 |
| Hale 5Ssw #2, MI | 816 ft | May 23 | Sep 26 |
Frost dates near South Branch
- Long Lake, MI 48743 · last May 21, first Sep 29
- Hale, MI 48739 · last May 16, first Oct 5
- Lupton, MI 48635 · last May 21, first Sep 29
- Glennie, MI 48737 · last May 19, first Sep 29
- Rose City, MI 48654 · last May 21, first Sep 29
- National City, MI 48748 · last May 16, first Oct 5
- Curran, MI 48728 · last May 19, first Oct 2
- Mio, MI 48647 · last May 19, first Oct 2
Frequently asked questions
- When is the last frost in South Branch, MI?
- For ZIP code 48761, the average last spring frost (32°F) is May 21, based on NOAA 1991-2020 climate normals for the Lupton 1S, MI weather station. There is a 1-in-10 chance of a frost after June 5.
- When is the first frost in South Branch, MI?
- The average first fall frost (32°F) is September 29. There is a 1-in-10 chance of frost by September 15, so tender plants are at risk from that point on.
- How long is the growing season in 48761?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 129 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.