Frost dates for 03580Franconia, NH
The average last spring frost in Franconia is May 24 and the average first fall frost is September 18, giving a typical growing season of about 116 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 24
- Average first fall frost
- Sep 18
- Growing season
- 116 days
Safer after Jun 8 (1-in-10 risk)
Possible by Sep 6 (1-in-10 risk)
Last frost typically in 204 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 22 · Jun 5 · Jun 24 | Aug 25 · Sep 7 · Sep 20 | 93 days | 100% |
| Frost / freeze (32°F) | May 6 · May 24 · Jun 8 | Sep 6 · Sep 18 · Oct 1 | 116 days | 100% |
| Hard freeze (28°F) | Apr 24 · May 7 · May 27 | Sep 15 · Sep 30 · Oct 14 | 142 days | 100% |
Planting calendar for Franconia
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 23 – Jun 29 |
| Tomatoes | Transplant outdoors | Jun 9 – May 29 |
| Peppers | Start seeds indoors | Apr 23 – May 24 |
| Peppers | Transplant outdoors | Jun 23 – Jul 24 |
| Eggplant | Start seeds indoors | May 10 – Jun 8 |
| Eggplant | Transplant outdoors | Jun 23 – Jul 24 |
| Cucumbers | Sow outdoors | Jun 23 – Jun 8 |
| Summer squash | Sow outdoors | Jun 9 – Jul 24 |
| Winter squash & pumpkins | Sow outdoors | Jun 23 – Jul 24 |
| Snap beans | Sow outdoors | Jun 9 – Jul 1 |
| Sweet corn | Sow outdoors | Jun 9 – May 29 |
| Watermelon & cantaloupe | Sow outdoors | Jun 23 – Jul 24 |
| Okra | Sow outdoors | Jun 16 – Jul 9 |
| Peas | Sow outdoors (spring) | Apr 23 – Jun 8 |
| Potatoes | Plant outdoors (spring) | Apr 23 – Jun 23 |
| Onions | Start seeds indoors (spring) | Mar 12 – Apr 8 |
| Onions | Transplant outdoors (spring) | May 10 – Jun 8 |
| Broccoli | Start seeds indoors (spring) | Apr 5 – May 9 |
| Broccoli | Transplant outdoors (spring) | May 10 – Jun 8 |
| Broccoli | Start seeds indoors (fall) | May 19 – May 29 |
| Broccoli | Transplant outdoors (fall) | Jun 18 – Jun 29 |
| Cabbage | Start seeds indoors (spring) | Mar 26 – Apr 23 |
| Cabbage | Transplant outdoors (spring) | Apr 23 – May 24 |
| Cabbage | Start seeds indoors (fall) | May 9 – Jun 8 |
| Cabbage | Transplant outdoors (fall) | Jun 8 – Jul 9 |
| Leaf lettuce | Sow outdoors (spring) | Apr 23 – Jul 9 |
| Leaf lettuce | Sow outdoors (fall) | Jun 8 – Jul 25 |
| Spinach | Sow outdoors (spring) | Apr 16 – May 30 |
| Spinach | Sow outdoors (fall) | Jun 25 – Jul 30 |
| Radishes | Sow outdoors (spring) | Apr 23 – Jun 13 |
| Radishes | Sow outdoors (fall) | Jun 8 – Aug 9 |
| Kale | Sow outdoors (spring) | May 10 – May 30 |
| Kale | Sow outdoors (fall) | Jun 1 – Jul 9 |
| Carrots | Sow outdoors (spring) | May 24 – Jul 9 |
| Carrots | Sow outdoors (fall) | May 9 – Jun 24 |
| Garlic | Plant outdoors (fall) | Sep 8 – Oct 9 |
Where these dates come from
ZIP code 03580 is matched to the NOAA station Bethlehem 2, NH, 13.5 km away, at 1,180 ft elevation (239 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Bethlehem 2, NH (used) | 1,180 ft | May 24 | Sep 18 |
| Lincoln Nepp, NH | 807 ft | May 7 | Oct 4 |
| Whitefield Mt Washington Ap, NH | 1,074 ft | May 27 | Sep 19 |
| Benton 5 Sw, NH | 1,200 ft | May 15 | Sep 28 |
Frost dates near Franconia
- Sugar Hill, NH 03586 · last May 24, first Sep 18
- Bethlehem, NH 03574 · last May 24, first Sep 18
- Lisbon, NH 03585 · last May 13, first Oct 3
- Littleton, NH 03561 · last May 24, first Sep 18
- Lincoln, NH 03251 · last May 15, first Sep 28
- Twin Mountain, NH 03595 · last May 24, first Sep 18
- Bath, NH 03740 · last May 10, first Oct 3
- North Woodstock, NH 03262 · last May 7, first Oct 4
Frequently asked questions
- When is the last frost in Franconia, NH?
- For ZIP code 03580, the average last spring frost (32°F) is May 24, based on NOAA 1991-2020 climate normals for the Bethlehem 2, NH weather station. There is a 1-in-10 chance of a frost after June 8.
- When is the first frost in Franconia, NH?
- The average first fall frost (32°F) is September 18. There is a 1-in-10 chance of frost by September 6, so tender plants are at risk from that point on.
- How long is the growing season in 03580?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 116 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.