Frost dates for 04668Princeton, ME
The average last spring frost in Princeton is May 4 and the average first fall frost is October 10, giving a typical growing season of about 157 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 4
- Average first fall frost
- Oct 10
- Growing season
- 157 days
Safer after May 18 (1-in-10 risk)
Possible by Oct 1 (1-in-10 risk)
Last frost typically in 184 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 3 · May 17 · Jun 1 | Sep 20 · Oct 1 · Oct 11 | 135 days | 100% |
| Frost / freeze (32°F) | Apr 24 · May 4 · May 18 | Oct 1 · Oct 10 · Oct 23 | 157 days | 100% |
| Hard freeze (28°F) | Apr 10 · Apr 24 · May 6 | Oct 9 · Oct 24 · Nov 6 | 182 days | 100% |
Planting calendar for Princeton
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 3 – Jun 9 |
| Tomatoes | Transplant outdoors | May 20 – Jun 20 |
| Peppers | Start seeds indoors | Apr 3 – May 4 |
| Peppers | Transplant outdoors | Jun 3 – Jul 4 |
| Eggplant | Start seeds indoors | Apr 20 – May 19 |
| Eggplant | Transplant outdoors | Jun 3 – Jul 4 |
| Cucumbers | Sow outdoors | Jun 3 – Jun 30 |
| Summer squash | Sow outdoors | May 20 – Jul 4 |
| Winter squash & pumpkins | Sow outdoors | Jun 3 – Jul 4 |
| Snap beans | Sow outdoors | May 20 – Jul 23 |
| Sweet corn | Sow outdoors | May 20 – Jun 20 |
| Watermelon & cantaloupe | Sow outdoors | Jun 3 – Jul 4 |
| Okra | Sow outdoors | May 27 – Jun 19 |
| Peas | Sow outdoors (spring) | Apr 3 – May 19 |
| Potatoes | Plant outdoors (spring) | Apr 3 – Jun 3 |
| Onions | Start seeds indoors (spring) | Feb 20 – Mar 19 |
| Onions | Transplant outdoors (spring) | Apr 20 – May 19 |
| Broccoli | Start seeds indoors (spring) | Mar 16 – Apr 19 |
| Broccoli | Transplant outdoors (spring) | Apr 20 – May 19 |
| Broccoli | Start seeds indoors (fall) | Jun 10 – Jun 20 |
| Broccoli | Transplant outdoors (fall) | Jul 10 – Jul 21 |
| Cabbage | Start seeds indoors (spring) | Mar 6 – Apr 3 |
| Cabbage | Transplant outdoors (spring) | Apr 3 – May 4 |
| Cabbage | Start seeds indoors (fall) | May 31 – Jun 30 |
| Cabbage | Transplant outdoors (fall) | Jun 30 – Jul 31 |
| Leaf lettuce | Sow outdoors (spring) | Apr 3 – Jun 19 |
| Leaf lettuce | Sow outdoors (fall) | Jun 30 – Aug 16 |
| Spinach | Sow outdoors (spring) | Mar 27 – May 10 |
| Spinach | Sow outdoors (fall) | Jul 17 – Aug 21 |
| Radishes | Sow outdoors (spring) | Apr 3 – May 24 |
| Radishes | Sow outdoors (fall) | Jun 30 – Aug 31 |
| Kale | Sow outdoors (spring) | Apr 20 – May 10 |
| Kale | Sow outdoors (fall) | Jun 23 – Jul 31 |
| Carrots | Sow outdoors (spring) | May 4 – Jun 19 |
| Carrots | Sow outdoors (fall) | May 31 – Jul 16 |
| Garlic | Plant outdoors (fall) | Sep 30 – Oct 31 |
Where these dates come from
ZIP code 04668 is matched to the NOAA station Grand Lake Stream, ME, 14.2 km away, at 290 ft elevation (87 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Grand Lake Stream, ME (used) | 290 ft | May 4 | Oct 10 |
| Woodland, ME | 123 ft | Apr 21 | Oct 26 |
| Topsfield 2, ME | 620 ft | May 6 | Oct 8 |
| Wesley, ME | 410 ft | May 2 | Oct 15 |
Frost dates near Princeton
- Grand Lake Stream, ME 04637 · last May 4, first Oct 10
- Baileyville, ME 04694 · last Apr 21, first Oct 26
- Waite, ME 04492 · last May 6, first Oct 8
- Wesley, ME 04686 · last May 4, first Oct 10
- Topsfield, ME 04490 · last May 6, first Oct 8
- Calais, ME 04619 · last Apr 21, first Oct 26
- Meddybemps, ME 04657 · last Apr 21, first Oct 26
- Lambert Lake, ME 04454 · last May 13, first Oct 1
Frequently asked questions
- When is the last frost in Princeton, ME?
- For ZIP code 04668, the average last spring frost (32°F) is May 4, based on NOAA 1991-2020 climate normals for the Grand Lake Stream, ME weather station. There is a 1-in-10 chance of a frost after May 18.
- When is the first frost in Princeton, ME?
- The average first fall frost (32°F) is October 10. 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 04668?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 157 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.