Frost dates for 04730Houlton, ME
The average last spring frost in Houlton is May 27 and the average first fall frost is September 18, giving a typical growing season of about 115 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 27
- Average first fall frost
- Sep 18
- Growing season
- 115 days
Safer after Jun 10 (1-in-10 risk)
Possible by Sep 5 (1-in-10 risk)
Last frost typically in 207 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 27 · Jun 10 · Jun 28 | Aug 24 · Sep 7 · Sep 21 | 89 days | 100% |
| Frost / freeze (32°F) | May 9 · May 27 · Jun 10 | Sep 5 · Sep 18 · Oct 2 | 115 days | 100% |
| Hard freeze (28°F) | Apr 28 · May 10 · May 28 | Sep 18 · Oct 1 · Oct 15 | 143 days | 100% |
Planting calendar for Houlton
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 26 – Jul 2 |
| Tomatoes | Transplant outdoors | Jun 12 – May 29 |
| Peppers | Start seeds indoors | Apr 26 – May 27 |
| Peppers | Transplant outdoors | Jun 26 – Jul 27 |
| Eggplant | Start seeds indoors | May 13 – Jun 11 |
| Eggplant | Transplant outdoors | Jun 26 – Jul 27 |
| Cucumbers | Sow outdoors | Jun 26 – Jun 8 |
| Summer squash | Sow outdoors | Jun 12 – Jul 27 |
| Winter squash & pumpkins | Sow outdoors | Jun 26 – Jul 27 |
| Snap beans | Sow outdoors | Jun 12 – Jul 1 |
| Sweet corn | Sow outdoors | Jun 12 – May 29 |
| Watermelon & cantaloupe | Sow outdoors | Jun 26 – Jul 27 |
| Okra | Sow outdoors | Jun 19 – Jul 12 |
| Peas | Sow outdoors (spring) | Apr 26 – Jun 11 |
| Potatoes | Plant outdoors (spring) | Apr 26 – Jun 26 |
| Onions | Start seeds indoors (spring) | Mar 15 – Apr 11 |
| Onions | Transplant outdoors (spring) | May 13 – Jun 11 |
| Broccoli | Start seeds indoors (spring) | Apr 8 – May 12 |
| Broccoli | Transplant outdoors (spring) | May 13 – Jun 11 |
| Broccoli | Start seeds indoors (fall) | May 19 – May 29 |
| Broccoli | Transplant outdoors (fall) | Jun 18 – Jun 29 |
| Cabbage | Start seeds indoors (spring) | Mar 29 – Apr 26 |
| Cabbage | Transplant outdoors (spring) | Apr 26 – May 27 |
| Cabbage | Start seeds indoors (fall) | May 9 – Jun 8 |
| Cabbage | Transplant outdoors (fall) | Jun 8 – Jul 9 |
| Leaf lettuce | Sow outdoors (spring) | Apr 26 – Jul 12 |
| Leaf lettuce | Sow outdoors (fall) | Jun 8 – Jul 25 |
| Spinach | Sow outdoors (spring) | Apr 19 – Jun 2 |
| Spinach | Sow outdoors (fall) | Jun 25 – Jul 30 |
| Radishes | Sow outdoors (spring) | Apr 26 – Jun 16 |
| Radishes | Sow outdoors (fall) | Jun 8 – Aug 9 |
| Kale | Sow outdoors (spring) | May 13 – Jun 2 |
| Kale | Sow outdoors (fall) | Jun 1 – Jul 9 |
| Carrots | Sow outdoors (spring) | May 27 – Jul 12 |
| Carrots | Sow outdoors (fall) | May 9 – Jun 24 |
| Garlic | Plant outdoors (fall) | Sep 8 – Oct 9 |
Where these dates come from
ZIP code 04730 is matched to the NOAA station Houlton Intl Ap, ME, 5.4 km away, at 476 ft elevation (82 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Houlton Intl Ap, ME (used) | 476 ft | May 27 | Sep 18 |
| Houlton 5N, ME | 390 ft | May 19 | Sep 23 |
| Bridgewater, ME | 420 ft | May 25 | Sep 18 |
| Patten 2, ME | 820 ft | May 13 | Sep 30 |
Frost dates near Houlton
- New Limerick, ME 04761 · last May 27, first Sep 18
- Monticello, ME 04760 · last May 19, first Sep 23
- Oakfield, ME 04763 · last May 27, first Sep 18
- Orient, ME 04471 · last May 27, first Sep 18
- Smyrna Mills, ME 04780 · last May 13, first Sep 30
- Island Falls, ME 04747 · last May 13, first Sep 30
- Bridgewater, ME 04735 · last May 25, first Sep 18
- Blaine, ME 04734 · last May 25, first Sep 18
Frequently asked questions
- When is the last frost in Houlton, ME?
- For ZIP code 04730, the average last spring frost (32°F) is May 27, based on NOAA 1991-2020 climate normals for the Houlton Intl Ap, ME weather station. There is a 1-in-10 chance of a frost after June 10.
- When is the first frost in Houlton, ME?
- The average first fall frost (32°F) is September 18. There is a 1-in-10 chance of frost by September 5, so tender plants are at risk from that point on.
- How long is the growing season in 04730?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 115 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.