Frost dates for 83825Dover, ID
The average last spring frost in Dover is May 8 and the average first fall frost is September 28, giving a typical growing season of about 141 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 8
- Average first fall frost
- Sep 28
- Growing season
- 141 days
Safer after May 25 (1-in-10 risk)
Possible by Sep 11 (1-in-10 risk)
Last frost typically in 187 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 11 · May 28 · Jun 17 | Sep 1 · Sep 13 · Sep 27 | 109 days | 100% |
| Frost / freeze (32°F) | Apr 23 · May 8 · May 25 | Sep 11 · Sep 28 · Oct 11 | 141 days | 100% |
| Hard freeze (28°F) | Mar 31 · Apr 21 · May 7 | Sep 25 · Oct 10 · Oct 29 | 172 days | 100% |
Planting calendar for Dover
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 7 – Jun 13 |
| Tomatoes | Transplant outdoors | May 24 – Jun 8 |
| Peppers | Start seeds indoors | Apr 7 – May 8 |
| Peppers | Transplant outdoors | Jun 7 – Jul 8 |
| Eggplant | Start seeds indoors | Apr 24 – May 23 |
| Eggplant | Transplant outdoors | Jun 7 – Jul 8 |
| Cucumbers | Sow outdoors | Jun 7 – Jun 18 |
| Summer squash | Sow outdoors | May 24 – Jul 8 |
| Winter squash & pumpkins | Sow outdoors | Jun 7 – Jul 8 |
| Snap beans | Sow outdoors | May 24 – Jul 11 |
| Sweet corn | Sow outdoors | May 24 – Jun 8 |
| Watermelon & cantaloupe | Sow outdoors | Jun 7 – Jul 8 |
| Okra | Sow outdoors | May 31 – Jun 23 |
| Peas | Sow outdoors (spring) | Apr 7 – May 23 |
| Potatoes | Plant outdoors (spring) | Apr 7 – Jun 7 |
| Onions | Start seeds indoors (spring) | Feb 24 – Mar 23 |
| Onions | Transplant outdoors (spring) | Apr 24 – May 23 |
| Broccoli | Start seeds indoors (spring) | Mar 20 – Apr 23 |
| Broccoli | Transplant outdoors (spring) | Apr 24 – May 23 |
| Broccoli | Start seeds indoors (fall) | May 29 – Jun 8 |
| Broccoli | Transplant outdoors (fall) | Jun 28 – Jul 9 |
| Cabbage | Start seeds indoors (spring) | Mar 10 – Apr 7 |
| Cabbage | Transplant outdoors (spring) | Apr 7 – May 8 |
| Cabbage | Start seeds indoors (fall) | May 19 – Jun 18 |
| Cabbage | Transplant outdoors (fall) | Jun 18 – Jul 19 |
| Leaf lettuce | Sow outdoors (spring) | Apr 7 – Jun 23 |
| Leaf lettuce | Sow outdoors (fall) | Jun 18 – Aug 4 |
| Spinach | Sow outdoors (spring) | Mar 31 – May 14 |
| Spinach | Sow outdoors (fall) | Jul 5 – Aug 9 |
| Radishes | Sow outdoors (spring) | Apr 7 – May 28 |
| Radishes | Sow outdoors (fall) | Jun 18 – Aug 19 |
| Kale | Sow outdoors (spring) | Apr 24 – May 14 |
| Kale | Sow outdoors (fall) | Jun 11 – Jul 19 |
| Carrots | Sow outdoors (spring) | May 8 – Jun 23 |
| Carrots | Sow outdoors (fall) | May 19 – Jul 4 |
| Garlic | Plant outdoors (fall) | Sep 18 – Oct 19 |
Where these dates come from
ZIP code 83825 is matched to the NOAA station Sandpoint Exp Stn, ID, 5.9 km away, at 2,126 ft elevation (46 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Sandpoint Exp Stn, ID (used) | 2,126 ft | May 8 | Sep 28 |
| Priest Rvr Exp Stn, ID | 2,371 ft | May 20 | Sep 13 |
| Bayview Model Basin, ID | 2,087 ft | May 22 | Sep 22 |
| Newport, WA | 2,162 ft | May 12 | Sep 21 |
Frost dates near Dover
- Sagle, ID 83860 · last May 8, first Sep 28
- Ponderay, ID 83852 · last May 8, first Sep 28
- Sandpoint, ID 83864 · last May 8, first Sep 28
- Kootenai, ID 83840 · last May 8, first Sep 28
- Colburn, ID 83865 · last May 20, first Sep 13
- Laclede, ID 83841 · last May 8, first Sep 28
- Cocolalla, ID 83813 · last May 20, first Sep 13
- Careywood, ID 83809 · last May 22, first Sep 22
Frequently asked questions
- When is the last frost in Dover, ID?
- For ZIP code 83825, the average last spring frost (32°F) is May 8, based on NOAA 1991-2020 climate normals for the Sandpoint Exp Stn, ID weather station. There is a 1-in-10 chance of a frost after May 25.
- When is the first frost in Dover, ID?
- The average first fall frost (32°F) is September 28. There is a 1-in-10 chance of frost by September 11, so tender plants are at risk from that point on.
- How long is the growing season in 83825?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 141 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.