Frost dates for 49618Boon, MI
The average last spring frost in Boon is May 19 and the average first fall frost is October 1, giving a typical growing season of about 135 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 19
- Average first fall frost
- Oct 1
- Growing season
- 135 days
Safer after Jun 3 (1-in-10 risk)
Possible by Sep 17 (1-in-10 risk)
Last frost typically in 198 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 16 · May 31 · Jun 14 | Aug 31 · Sep 20 · Oct 4 | 112 days | 100% |
| Frost / freeze (32°F) | May 2 · May 19 · Jun 3 | Sep 17 · Oct 1 · Oct 16 | 135 days | 100% |
| Hard freeze (28°F) | Apr 21 · May 5 · May 21 | Sep 28 · Oct 13 · Oct 31 | 160 days | 100% |
Planting calendar for Boon
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 11 |
| 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 21 |
| Summer squash | Sow outdoors | Jun 4 – Jul 19 |
| Winter squash & pumpkins | Sow outdoors | Jun 18 – Jul 19 |
| Snap beans | Sow outdoors | Jun 4 – Jul 14 |
| Sweet corn | Sow outdoors | Jun 4 – Jun 11 |
| 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) | Jun 1 – Jun 11 |
| Broccoli | Transplant outdoors (fall) | Jul 1 – Jul 12 |
| Cabbage | Start seeds indoors (spring) | Mar 21 – Apr 18 |
| Cabbage | Transplant outdoors (spring) | Apr 18 – May 19 |
| Cabbage | Start seeds indoors (fall) | May 22 – Jun 21 |
| Cabbage | Transplant outdoors (fall) | Jun 21 – Jul 22 |
| Leaf lettuce | Sow outdoors (spring) | Apr 18 – Jul 4 |
| Leaf lettuce | Sow outdoors (fall) | Jun 21 – Aug 7 |
| Spinach | Sow outdoors (spring) | Apr 11 – May 25 |
| Spinach | Sow outdoors (fall) | Jul 8 – Aug 12 |
| Radishes | Sow outdoors (spring) | Apr 18 – Jun 8 |
| Radishes | Sow outdoors (fall) | Jun 21 – Aug 22 |
| Kale | Sow outdoors (spring) | May 5 – May 25 |
| Kale | Sow outdoors (fall) | Jun 14 – Jul 22 |
| Carrots | Sow outdoors (spring) | May 19 – Jul 4 |
| Carrots | Sow outdoors (fall) | May 22 – Jul 7 |
| Garlic | Plant outdoors (fall) | Sep 21 – Oct 22 |
Where these dates come from
ZIP code 49618 is matched to the NOAA station Cadillac, MI, 17.6 km away, at 1,295 ft elevation (149 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Cadillac, MI (used) | 1,295 ft | May 19 | Oct 1 |
| Cadillac 9&10 News, MI | 1,363 ft | May 15 | Oct 1 |
| Wellston 1N, MI | 773 ft | May 28 | Sep 25 |
| Lake City Exp Farm, MI | 1,230 ft | May 22 | Sep 26 |
Frost dates near Boon
- Harrietta, MI 49638 · last May 19, first Oct 1
- Mesick, MI 49668 · last May 7, first Oct 20
- Cadillac, MI 49601 · last May 19, first Oct 1
- Manton, MI 49663 · last May 19, first Oct 1
- Tustin, MI 49688 · last May 19, first Oct 1
- Buckley, MI 49620 · last May 24, first Oct 1
- Luther, MI 49656 · last May 19, first Oct 1
- Copemish, MI 49625 · last May 7, first Oct 20
Frequently asked questions
- When is the last frost in Boon, MI?
- For ZIP code 49618, the average last spring frost (32°F) is May 19, based on NOAA 1991-2020 climate normals for the Cadillac, MI weather station. There is a 1-in-10 chance of a frost after June 3.
- When is the first frost in Boon, MI?
- The average first fall frost (32°F) is October 1. There is a 1-in-10 chance of frost by September 17, so tender plants are at risk from that point on.
- How long is the growing season in 49618?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 135 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.