Frost dates for 03086Wilton, NH
The average last spring frost in Wilton is May 3 and the average first fall frost is October 5, giving a typical growing season of about 156 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 3
- Average first fall frost
- Oct 5
- Growing season
- 156 days
Safer after May 15 (1-in-10 risk)
Possible by Sep 25 (1-in-10 risk)
Last frost typically in 183 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 2 · May 13 · May 25 | Sep 16 · Sep 28 · Oct 7 | 136 days | 100% |
| Frost / freeze (32°F) | Apr 22 · May 3 · May 15 | Sep 25 · Oct 5 · Oct 18 | 156 days | 100% |
| Hard freeze (28°F) | Apr 7 · Apr 20 · May 2 | Oct 3 · Oct 16 · Nov 1 | 179 days | 100% |
Planting calendar for Wilton
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 2 – Jun 8 |
| Tomatoes | Transplant outdoors | May 19 – Jun 15 |
| Peppers | Start seeds indoors | Apr 2 – May 3 |
| Peppers | Transplant outdoors | Jun 2 – Jul 3 |
| Eggplant | Start seeds indoors | Apr 19 – May 18 |
| Eggplant | Transplant outdoors | Jun 2 – Jul 3 |
| Cucumbers | Sow outdoors | Jun 2 – Jun 25 |
| Summer squash | Sow outdoors | May 19 – Jul 3 |
| Winter squash & pumpkins | Sow outdoors | Jun 2 – Jul 3 |
| Snap beans | Sow outdoors | May 19 – Jul 18 |
| Sweet corn | Sow outdoors | May 19 – Jun 15 |
| Watermelon & cantaloupe | Sow outdoors | Jun 2 – Jul 3 |
| Okra | Sow outdoors | May 26 – Jun 18 |
| Peas | Sow outdoors (spring) | Apr 2 – May 18 |
| Potatoes | Plant outdoors (spring) | Apr 2 – Jun 2 |
| Onions | Start seeds indoors (spring) | Feb 19 – Mar 18 |
| Onions | Transplant outdoors (spring) | Apr 19 – May 18 |
| Broccoli | Start seeds indoors (spring) | Mar 15 – Apr 18 |
| Broccoli | Transplant outdoors (spring) | Apr 19 – May 18 |
| Broccoli | Start seeds indoors (fall) | Jun 5 – Jun 15 |
| Broccoli | Transplant outdoors (fall) | Jul 5 – Jul 16 |
| Cabbage | Start seeds indoors (spring) | Mar 5 – Apr 2 |
| Cabbage | Transplant outdoors (spring) | Apr 2 – May 3 |
| Cabbage | Start seeds indoors (fall) | May 26 – Jun 25 |
| Cabbage | Transplant outdoors (fall) | Jun 25 – Jul 26 |
| Leaf lettuce | Sow outdoors (spring) | Apr 2 – Jun 18 |
| Leaf lettuce | Sow outdoors (fall) | Jun 25 – Aug 11 |
| Spinach | Sow outdoors (spring) | Mar 26 – May 9 |
| Spinach | Sow outdoors (fall) | Jul 12 – Aug 16 |
| Radishes | Sow outdoors (spring) | Apr 2 – May 23 |
| Radishes | Sow outdoors (fall) | Jun 25 – Aug 26 |
| Kale | Sow outdoors (spring) | Apr 19 – May 9 |
| Kale | Sow outdoors (fall) | Jun 18 – Jul 26 |
| Carrots | Sow outdoors (spring) | May 3 – Jun 18 |
| Carrots | Sow outdoors (fall) | May 26 – Jul 11 |
| Garlic | Plant outdoors (fall) | Sep 25 – Oct 26 |
Where these dates come from
ZIP code 03086 is matched to the NOAA station Milford, NH, 8.6 km away, at 320 ft elevation (271 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Milford, NH (used) | 320 ft | May 3 | Oct 5 |
| Greenville 1 Nne, NH | 900 ft | May 10 | Oct 6 |
| E Milford, NH | 240 ft | Apr 28 | Oct 8 |
| Jaffrey Muni Ap, NH | 1,040 ft | May 5 | Oct 6 |
Frost dates near Wilton
- Lyndeborough, NH 03082 · last May 5, first Oct 6
- Milford, NH 03055 · last May 3, first Oct 5
- Temple, NH 03084 · last May 5, first Oct 6
- Mont Vernon, NH 03057 · last May 3, first Oct 5
- Greenville, NH 03048 · last May 10, first Oct 6
- Amherst, NH 03031 · last May 3, first Oct 5
- Brookline, NH 03033 · last May 3, first Oct 5
- New Ipswich, NH 03071 · last May 5, first Oct 6
Frequently asked questions
- When is the last frost in Wilton, NH?
- For ZIP code 03086, the average last spring frost (32°F) is May 3, based on NOAA 1991-2020 climate normals for the Milford, NH weather station. There is a 1-in-10 chance of a frost after May 15.
- When is the first frost in Wilton, NH?
- The average first fall frost (32°F) is October 5. There is a 1-in-10 chance of frost by September 25, so tender plants are at risk from that point on.
- How long is the growing season in 03086?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 156 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.