Frost dates for 48895Williamston, MI
The average last spring frost in Williamston is April 28 and the average first fall frost is October 17, giving a typical growing season of about 173 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 28
- Average first fall frost
- Oct 17
- Growing season
- 173 days
Safer after May 16 (1-in-10 risk)
Possible by Oct 1 (1-in-10 risk)
Last frost typically in 176 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 23 · May 8 · May 27 | Sep 22 · Oct 4 · Oct 18 | 149 days | 100% |
| Frost / freeze (32°F) | Apr 13 · Apr 28 · May 16 | Oct 1 · Oct 17 · Nov 1 | 173 days | 100% |
| Hard freeze (28°F) | Apr 2 · Apr 15 · May 1 | Oct 14 · Oct 30 · Nov 13 | 198 days | 100% |
Planting calendar for Williamston
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 28 – Jun 3 |
| Tomatoes | Transplant outdoors | May 14 – Jun 27 |
| Peppers | Start seeds indoors | Mar 28 – Apr 28 |
| Peppers | Transplant outdoors | May 28 – Jun 28 |
| Eggplant | Start seeds indoors | Apr 14 – May 13 |
| Eggplant | Transplant outdoors | May 28 – Jun 28 |
| Cucumbers | Sow outdoors | May 28 – Jul 7 |
| Summer squash | Sow outdoors | May 14 – Jun 28 |
| Winter squash & pumpkins | Sow outdoors | May 28 – Jun 28 |
| Snap beans | Sow outdoors | May 14 – Jul 30 |
| Sweet corn | Sow outdoors | May 14 – Jun 27 |
| Watermelon & cantaloupe | Sow outdoors | May 28 – Jun 28 |
| Okra | Sow outdoors | May 21 – Jun 13 |
| Peas | Sow outdoors (spring) | Mar 28 – May 13 |
| Potatoes | Plant outdoors (spring) | Mar 28 – May 28 |
| Onions | Start seeds indoors (spring) | Feb 14 – Mar 13 |
| Onions | Transplant outdoors (spring) | Apr 14 – May 13 |
| Broccoli | Start seeds indoors (spring) | Mar 10 – Apr 13 |
| Broccoli | Transplant outdoors (spring) | Apr 14 – May 13 |
| Broccoli | Start seeds indoors (fall) | Jun 17 – Jun 27 |
| Broccoli | Transplant outdoors (fall) | Jul 17 – Jul 28 |
| Cabbage | Start seeds indoors (spring) | Feb 28 – Mar 28 |
| Cabbage | Transplant outdoors (spring) | Mar 28 – Apr 28 |
| Cabbage | Start seeds indoors (fall) | Jun 7 – Jul 7 |
| Cabbage | Transplant outdoors (fall) | Jul 7 – Aug 7 |
| Leaf lettuce | Sow outdoors (spring) | Mar 28 – Jun 13 |
| Leaf lettuce | Sow outdoors (fall) | Jul 7 – Aug 23 |
| Spinach | Sow outdoors (spring) | Mar 21 – May 4 |
| Spinach | Sow outdoors (fall) | Jul 24 – Aug 28 |
| Radishes | Sow outdoors (spring) | Mar 28 – May 18 |
| Radishes | Sow outdoors (fall) | Jul 7 – Sep 7 |
| Kale | Sow outdoors (spring) | Apr 14 – May 4 |
| Kale | Sow outdoors (fall) | Jun 30 – Aug 7 |
| Carrots | Sow outdoors (spring) | Apr 28 – Jun 13 |
| Carrots | Sow outdoors (fall) | Jun 7 – Jul 23 |
| Garlic | Plant outdoors (fall) | Oct 7 – Nov 7 |
Where these dates come from
ZIP code 48895 is matched to the NOAA station East Lansing 4 S, MI, 15.9 km away, at 880 ft elevation (6 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| East Lansing 4 S, MI (used) | 880 ft | Apr 28 | Oct 17 |
| Lansing Capital City Ap, MI | 841 ft | May 1 | Oct 13 |
| Howell Wwtp, MI | 917 ft | May 4 | Oct 7 |
| Durand Wwtp, MI | 770 ft | May 3 | Oct 11 |
Frost dates near Williamston
- Okemos, MI 48864 · last Apr 28, first Oct 17
- Webberville, MI 48892 · last Apr 28, first Oct 17
- Haslett, MI 48840 · last Apr 28, first Oct 17
- Shaftsburg, MI 48882 · last Apr 28, first Oct 17
- East Lansing, MI 48825 · last Apr 28, first Oct 17
- Perry, MI 48872 · last Apr 28, first Oct 17
- Dansville, MI 48819 · last Apr 28, first Oct 17
- Morrice, MI 48857 · last May 3, first Oct 11
Frequently asked questions
- When is the last frost in Williamston, MI?
- For ZIP code 48895, the average last spring frost (32°F) is April 28, based on NOAA 1991-2020 climate normals for the East Lansing 4 S, MI weather station. There is a 1-in-10 chance of a frost after May 16.
- When is the first frost in Williamston, MI?
- The average first fall frost (32°F) is October 17. There is a 1-in-10 chance of frost by October 1, so tender plants are at risk from that point on.
- How long is the growing season in 48895?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 173 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.