Frost dates for 83615Donnelly, ID
The average last spring frost in Donnelly is May 30 and the average first fall frost is September 19, giving a typical growing season of about 110 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 30
- Average first fall frost
- Sep 19
- Growing season
- 110 days
Safer after Jun 21 (1-in-10 risk)
Possible by Sep 3 (1-in-10 risk)
Last frost typically in 208 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) | — | — | 76 days | 100% |
| Frost / freeze (32°F) | May 10 · May 30 · Jun 21 | Sep 3 · Sep 19 · Oct 4 | 110 days | 100% |
| Hard freeze (28°F) | Apr 21 · May 6 · May 28 | Sep 15 · Oct 2 · Oct 18 | 147 days | 100% |
Planting calendar for Donnelly
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 29 – Jul 5 |
| Tomatoes | Transplant outdoors | Jun 15 – May 30 |
| Peppers | Start seeds indoors | Apr 29 – May 30 |
| Peppers | Transplant outdoors | Jun 29 – Jul 30 |
| Eggplant | Start seeds indoors | May 16 – Jun 14 |
| Eggplant | Transplant outdoors | Jun 29 – Jul 30 |
| Cucumbers | Sow outdoors | Jun 29 – Jun 9 |
| Summer squash | Sow outdoors | Jun 15 – Jul 30 |
| Winter squash & pumpkins | Sow outdoors | Jun 29 – Jul 30 |
| Snap beans | Sow outdoors | Jun 15 – Jul 2 |
| Sweet corn | Sow outdoors | Jun 15 – May 30 |
| Watermelon & cantaloupe | Sow outdoors | Jun 29 – Jul 30 |
| Okra | Sow outdoors | Jun 22 – Jul 15 |
| Peas | Sow outdoors (spring) | Apr 29 – Jun 14 |
| Potatoes | Plant outdoors (spring) | Apr 29 – Jun 29 |
| Onions | Start seeds indoors (spring) | Mar 18 – Apr 14 |
| Onions | Transplant outdoors (spring) | May 16 – Jun 14 |
| Broccoli | Start seeds indoors (spring) | Apr 11 – May 15 |
| Broccoli | Transplant outdoors (spring) | May 16 – Jun 14 |
| Broccoli | Start seeds indoors (fall) | May 20 – May 30 |
| Broccoli | Transplant outdoors (fall) | Jun 19 – Jun 30 |
| Cabbage | Start seeds indoors (spring) | Apr 1 – Apr 29 |
| Cabbage | Transplant outdoors (spring) | Apr 29 – May 30 |
| Cabbage | Start seeds indoors (fall) | May 10 – Jun 9 |
| Cabbage | Transplant outdoors (fall) | Jun 9 – Jul 10 |
| Leaf lettuce | Sow outdoors (spring) | Apr 29 – Jul 15 |
| Leaf lettuce | Sow outdoors (fall) | Jun 9 – Jul 26 |
| Spinach | Sow outdoors (spring) | Apr 22 – Jun 5 |
| Spinach | Sow outdoors (fall) | Jun 26 – Jul 31 |
| Radishes | Sow outdoors (spring) | Apr 29 – Jun 19 |
| Radishes | Sow outdoors (fall) | Jun 9 – Aug 10 |
| Kale | Sow outdoors (spring) | May 16 – Jun 5 |
| Kale | Sow outdoors (fall) | Jun 2 – Jul 10 |
| Carrots | Sow outdoors (spring) | May 30 – Jul 15 |
| Carrots | Sow outdoors (fall) | May 10 – Jun 25 |
| Garlic | Plant outdoors (fall) | Sep 9 – Oct 10 |
Where these dates come from
ZIP code 83615 is matched to the NOAA station Cascade 1 Nw, ID, 15.9 km away, at 4,896 ft elevation (88 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Cascade 1 Nw, ID (used) | 4,896 ft | May 30 | Sep 19 |
| Mccall, ID | 5,025 ft | Jun 22 | Sep 2 |
| Mccall Ap, ID | 5,013 ft | Jun 10 | Sep 10 |
| Council, ID | 2,943 ft | May 10 | Oct 2 |
Frost dates near Donnelly
- Lake Fork, ID 83635 · last Jun 10, first Sep 10
- McCall, ID 83638 · last Jun 22, first Sep 2
- Cascade, ID 83611 · last —, first —
- Mesa, ID 83643 · last May 10, first Oct 2
- Council, ID 83612 · last May 10, first Oct 2
- Indian Valley, ID 83632 · last May 15, first Sep 27
- New Meadows, ID 83654 · last —, first —
- Ola, ID 83657 · last May 31, first Sep 16
Frequently asked questions
- When is the last frost in Donnelly, ID?
- For ZIP code 83615, the average last spring frost (32°F) is May 30, based on NOAA 1991-2020 climate normals for the Cascade 1 Nw, ID weather station. There is a 1-in-10 chance of a frost after June 21.
- When is the first frost in Donnelly, ID?
- The average first fall frost (32°F) is September 19. There is a 1-in-10 chance of frost by September 3, so tender plants are at risk from that point on.
- How long is the growing season in 83615?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 110 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.