Frost dates for 48737Glennie, MI
The average last spring frost in Glennie is May 19 and the average first fall frost is September 29, giving a typical growing season of about 133 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 19
- Average first fall frost
- Sep 29
- Growing season
- 133 days
Safer after Jun 2 (1-in-10 risk)
Possible by Sep 16 (1-in-10 risk)
Last frost typically in 199 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 19 · Jun 1 · Jun 19 | Sep 5 · Sep 18 · Oct 1 | 108 days | 100% |
| Frost / freeze (32°F) | May 3 · May 19 · Jun 2 | Sep 16 · Sep 29 · Oct 13 | 133 days | 100% |
| Hard freeze (28°F) | Apr 23 · May 4 · May 19 | Sep 27 · Oct 12 · Oct 26 | 157 days | 100% |
Planting calendar for Glennie
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 18 – Jun 24 |
| Tomatoes | Transplant outdoors | Jun 4 – Jun 9 |
| Peppers | Start seeds indoors | Apr 18 – May 19 |
| Peppers | Transplant outdoors | Jun 18 – Jul 19 |
| Eggplant | Start seeds indoors | May 5 – Jun 3 |
| Eggplant | Transplant outdoors | Jun 18 – Jul 19 |
| Cucumbers | Sow outdoors | Jun 18 – Jun 19 |
| Summer squash | Sow outdoors | Jun 4 – Jul 19 |
| Winter squash & pumpkins | Sow outdoors | Jun 18 – Jul 19 |
| Snap beans | Sow outdoors | Jun 4 – Jul 12 |
| Sweet corn | Sow outdoors | Jun 4 – Jun 9 |
| Watermelon & cantaloupe | Sow outdoors | Jun 18 – Jul 19 |
| Okra | Sow outdoors | Jun 11 – Jul 4 |
| Peas | Sow outdoors (spring) | Apr 18 – Jun 3 |
| Potatoes | Plant outdoors (spring) | Apr 18 – Jun 18 |
| Onions | Start seeds indoors (spring) | Mar 7 – Apr 3 |
| Onions | Transplant outdoors (spring) | May 5 – Jun 3 |
| Broccoli | Start seeds indoors (spring) | Mar 31 – May 4 |
| Broccoli | Transplant outdoors (spring) | May 5 – Jun 3 |
| Broccoli | Start seeds indoors (fall) | May 30 – Jun 9 |
| Broccoli | Transplant outdoors (fall) | Jun 29 – Jul 10 |
| Cabbage | Start seeds indoors (spring) | Mar 21 – Apr 18 |
| Cabbage | Transplant outdoors (spring) | Apr 18 – May 19 |
| Cabbage | Start seeds indoors (fall) | May 20 – Jun 19 |
| Cabbage | Transplant outdoors (fall) | Jun 19 – Jul 20 |
| Leaf lettuce | Sow outdoors (spring) | Apr 18 – Jul 4 |
| Leaf lettuce | Sow outdoors (fall) | Jun 19 – Aug 5 |
| Spinach | Sow outdoors (spring) | Apr 11 – May 25 |
| Spinach | Sow outdoors (fall) | Jul 6 – Aug 10 |
| Radishes | Sow outdoors (spring) | Apr 18 – Jun 8 |
| Radishes | Sow outdoors (fall) | Jun 19 – Aug 20 |
| Kale | Sow outdoors (spring) | May 5 – May 25 |
| Kale | Sow outdoors (fall) | Jun 12 – Jul 20 |
| Carrots | Sow outdoors (spring) | May 19 – Jul 4 |
| Carrots | Sow outdoors (fall) | May 20 – Jul 5 |
| Garlic | Plant outdoors (fall) | Sep 19 – Oct 20 |
Where these dates come from
ZIP code 48737 is matched to the NOAA station Glennie 2Se, MI, 2.7 km away, at 894 ft elevation (25 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Glennie 2Se, MI (used) | 894 ft | May 19 | Sep 29 |
| Hale Loud Dam, MI | 728 ft | May 16 | Oct 5 |
| Hale 5Ssw #2, MI | 816 ft | May 23 | Sep 26 |
| Lupton 1S, MI | 908 ft | May 21 | Sep 29 |
Frost dates near Glennie
- South Branch, MI 48761 · last May 21, first Sep 29
- Barton City, MI 48705 · last May 16, first Oct 5
- Mikado, MI 48745 · last May 8, first Oct 16
- Long Lake, MI 48743 · last May 21, first Sep 29
- Curran, MI 48728 · last May 19, first Oct 2
- Hale, MI 48739 · last May 16, first Oct 5
- National City, MI 48748 · last May 16, first Oct 5
- Greenbush, MI 48738 · last May 8, first Oct 16
Frequently asked questions
- When is the last frost in Glennie, MI?
- For ZIP code 48737, the average last spring frost (32°F) is May 19, based on NOAA 1991-2020 climate normals for the Glennie 2Se, MI weather station. There is a 1-in-10 chance of a frost after June 2.
- When is the first frost in Glennie, MI?
- The average first fall frost (32°F) is September 29. There is a 1-in-10 chance of frost by September 16, so tender plants are at risk from that point on.
- How long is the growing season in 48737?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 133 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.