Frost dates for 04086Topsham, ME
The average last spring frost in Topsham is May 15 and the average first fall frost is October 2, giving a typical growing season of about 139 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 15
- Average first fall frost
- Oct 2
- Growing season
- 139 days
Safer after May 28 (1-in-10 risk)
Possible by Sep 20 (1-in-10 risk)
Last frost typically in 195 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 14 · May 28 · Jun 7 | Sep 9 · Sep 21 · Oct 2 | 116 days | 100% |
| Frost / freeze (32°F) | May 1 · May 15 · May 28 | Sep 20 · Oct 2 · Oct 15 | 139 days | 100% |
| Hard freeze (28°F) | Apr 22 · May 3 · May 16 | Oct 1 · Oct 13 · Oct 31 | 163 days | 100% |
Planting calendar for Topsham
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 14 – Jun 20 |
| Tomatoes | Transplant outdoors | May 31 – Jun 12 |
| Peppers | Start seeds indoors | Apr 14 – May 15 |
| Peppers | Transplant outdoors | Jun 14 – Jul 15 |
| Eggplant | Start seeds indoors | May 1 – May 30 |
| Eggplant | Transplant outdoors | Jun 14 – Jul 15 |
| Cucumbers | Sow outdoors | Jun 14 – Jun 22 |
| Summer squash | Sow outdoors | May 31 – Jul 15 |
| Winter squash & pumpkins | Sow outdoors | Jun 14 – Jul 15 |
| Snap beans | Sow outdoors | May 31 – Jul 15 |
| Sweet corn | Sow outdoors | May 31 – Jun 12 |
| Watermelon & cantaloupe | Sow outdoors | Jun 14 – Jul 15 |
| Okra | Sow outdoors | Jun 7 – Jun 30 |
| Peas | Sow outdoors (spring) | Apr 14 – May 30 |
| Potatoes | Plant outdoors (spring) | Apr 14 – Jun 14 |
| Onions | Start seeds indoors (spring) | Mar 3 – Mar 30 |
| Onions | Transplant outdoors (spring) | May 1 – May 30 |
| Broccoli | Start seeds indoors (spring) | Mar 27 – Apr 30 |
| Broccoli | Transplant outdoors (spring) | May 1 – May 30 |
| Broccoli | Start seeds indoors (fall) | Jun 2 – Jun 12 |
| Broccoli | Transplant outdoors (fall) | Jul 2 – Jul 13 |
| Cabbage | Start seeds indoors (spring) | Mar 17 – Apr 14 |
| Cabbage | Transplant outdoors (spring) | Apr 14 – May 15 |
| Cabbage | Start seeds indoors (fall) | May 23 – Jun 22 |
| Cabbage | Transplant outdoors (fall) | Jun 22 – Jul 23 |
| Leaf lettuce | Sow outdoors (spring) | Apr 14 – Jun 30 |
| Leaf lettuce | Sow outdoors (fall) | Jun 22 – Aug 8 |
| Spinach | Sow outdoors (spring) | Apr 7 – May 21 |
| Spinach | Sow outdoors (fall) | Jul 9 – Aug 13 |
| Radishes | Sow outdoors (spring) | Apr 14 – Jun 4 |
| Radishes | Sow outdoors (fall) | Jun 22 – Aug 23 |
| Kale | Sow outdoors (spring) | May 1 – May 21 |
| Kale | Sow outdoors (fall) | Jun 15 – Jul 23 |
| Carrots | Sow outdoors (spring) | May 15 – Jun 30 |
| Carrots | Sow outdoors (fall) | May 23 – Jul 8 |
| Garlic | Plant outdoors (fall) | Sep 22 – Oct 23 |
Where these dates come from
ZIP code 04086 is matched to the NOAA station Durham, ME, 12.9 km away, at 140 ft elevation (76 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Durham, ME (used) | 140 ft | May 15 | Oct 2 |
| Bath, ME | 25 ft | May 10 | Oct 6 |
| Brunswick Nas, ME | 70 ft | May 2 | Oct 10 |
| Wiscasset Ap, ME | 68 ft | May 8 | Oct 7 |
Frost dates near Topsham
- Bowdoinham, ME 04008 · last May 8, first Oct 7
- Bowdoin, ME 04287 · last May 15, first Oct 2
- Brunswick, ME 04011 · last May 15, first Oct 2
- Lisbon Falls, ME 04252 · last May 15, first Oct 2
- Bath, ME 04530 · last May 8, first Oct 7
- Woolwich, ME 04579 · last May 8, first Oct 7
- Lisbon, ME 04250 · last May 15, first Oct 2
- Richmond, ME 04357 · last May 1, first Oct 11
Frequently asked questions
- When is the last frost in Topsham, ME?
- For ZIP code 04086, the average last spring frost (32°F) is May 15, based on NOAA 1991-2020 climate normals for the Durham, ME weather station. There is a 1-in-10 chance of a frost after May 28.
- When is the first frost in Topsham, ME?
- The average first fall frost (32°F) is October 2. There is a 1-in-10 chance of frost by September 20, so tender plants are at risk from that point on.
- How long is the growing season in 04086?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 139 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.