Frost dates for 83602Banks, ID
The average last spring frost in Banks is June 1 and the average first fall frost is September 10, giving a typical growing season of about 102 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Jun 1
- Average first fall frost
- Sep 10
- Growing season
- 102 days
Safer after Jun 20 (1-in-10 risk)
Possible by Aug 28 (1-in-10 risk)
Last frost typically in 210 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) | — | — | 67 days | 100% |
| Frost / freeze (32°F) | May 13 · Jun 1 · Jun 20 | Aug 28 · Sep 10 · Sep 27 | 102 days | 100% |
| Hard freeze (28°F) | Apr 26 · May 11 · May 30 | Sep 8 · Sep 24 · Oct 10 | 136 days | 100% |
Planting calendar for Banks
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 | May 1 – Jul 7 |
| Tomatoes | Transplant outdoors | Jun 17 – May 21 |
| Peppers | Start seeds indoors | May 1 – Jun 1 |
| Peppers | Transplant outdoors | Jul 1 – Aug 1 |
| Eggplant | Start seeds indoors | May 18 – Jun 16 |
| Eggplant | Transplant outdoors | Jul 1 – Aug 1 |
| Cucumbers | Sow outdoors | Jul 1 – May 31 |
| Summer squash | Sow outdoors | Jun 17 – Aug 1 |
| Winter squash & pumpkins | Sow outdoors | Jul 1 – Aug 1 |
| Snap beans | Sow outdoors | Jun 17 – Jun 23 |
| Sweet corn | Sow outdoors | Jun 17 – May 21 |
| Watermelon & cantaloupe | Sow outdoors | Jul 1 – Aug 1 |
| Okra | Sow outdoors | Jun 24 – Jul 17 |
| Peas | Sow outdoors (spring) | May 1 – Jun 16 |
| Potatoes | Plant outdoors (spring) | May 1 – Jul 1 |
| Onions | Start seeds indoors (spring) | Mar 20 – Apr 16 |
| Onions | Transplant outdoors (spring) | May 18 – Jun 16 |
| Broccoli | Start seeds indoors (spring) | Apr 13 – May 17 |
| Broccoli | Transplant outdoors (spring) | May 18 – Jun 16 |
| Broccoli | Start seeds indoors (fall) | May 11 – May 21 |
| Broccoli | Transplant outdoors (fall) | Jun 10 – Jun 21 |
| Cabbage | Start seeds indoors (spring) | Apr 3 – May 1 |
| Cabbage | Transplant outdoors (spring) | May 1 – Jun 1 |
| Cabbage | Start seeds indoors (fall) | May 1 – May 31 |
| Cabbage | Transplant outdoors (fall) | May 31 – Jul 1 |
| Leaf lettuce | Sow outdoors (spring) | May 1 – Jul 17 |
| Leaf lettuce | Sow outdoors (fall) | May 31 – Jul 17 |
| Spinach | Sow outdoors (spring) | Apr 24 – Jun 7 |
| Spinach | Sow outdoors (fall) | Jun 17 – Jul 22 |
| Radishes | Sow outdoors (spring) | May 1 – Jun 21 |
| Radishes | Sow outdoors (fall) | May 31 – Aug 1 |
| Kale | Sow outdoors (spring) | May 18 – Jun 7 |
| Kale | Sow outdoors (fall) | May 24 – Jul 1 |
| Carrots | Sow outdoors (spring) | Jun 1 – Jul 17 |
| Carrots | Sow outdoors (fall) | May 1 – Jun 16 |
| Garlic | Plant outdoors (fall) | Aug 31 – Oct 1 |
Where these dates come from
ZIP code 83602 is matched to the NOAA station Garden Valley, ID, 12.6 km away, at 3,100 ft elevation (210 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Garden Valley, ID (used) | 3,100 ft | Jun 1 | Sep 10 |
| Ola, ID | 3,075 ft | May 31 | Sep 16 |
| Idaho City, ID | 3,965 ft | Jun 17 | Sep 5 |
| Emmett 2 E, ID | 2,390 ft | Apr 30 | Oct 17 |
Frost dates near Banks
- Placerville, ID 83666 · last Jun 17, first Sep 5
- Horseshoe Bend, ID 83629 · last Apr 30, first Oct 17
- Sweet, ID 83670 · last Apr 30, first Oct 17
- Ola, ID 83657 · last May 31, first Sep 16
- Garden Valley, ID 83622 · last Jun 17, first Sep 5
- Emmett, ID 83617 · last Apr 30, first Oct 17
- Mountain Home Afb, ID 83648 · last Apr 30, first Oct 17
- Idaho City, ID 83631 · last Jun 17, first Sep 5
Frequently asked questions
- When is the last frost in Banks, ID?
- For ZIP code 83602, the average last spring frost (32°F) is June 1, based on NOAA 1991-2020 climate normals for the Garden Valley, ID weather station. There is a 1-in-10 chance of a frost after June 20.
- When is the first frost in Banks, ID?
- The average first fall frost (32°F) is September 10. There is a 1-in-10 chance of frost by August 28, so tender plants are at risk from that point on.
- How long is the growing season in 83602?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 102 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.