Frost dates for 83802Avery, ID
The average last spring frost in Avery is May 12 and the average first fall frost is September 30, giving a typical growing season of about 138 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 12
- Average first fall frost
- Sep 30
- Growing season
- 138 days
Safer after Jun 19 (1-in-10 risk)
Possible by Sep 12 (1-in-10 risk)
Last frost typically in 197 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 14 · Jun 7 · Jul 6 | Aug 31 · Sep 15 · Oct 1 | 98 days | 100% |
| Frost / freeze (32°F) | Apr 26 · May 12 · Jun 19 | Sep 12 · Sep 30 · Oct 17 | 138 days | 100% |
| Hard freeze (28°F) | Apr 1 · Apr 24 · May 12 | Sep 27 · Oct 14 · Nov 4 | 175 days | 100% |
Planting calendar for Avery
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 11 – Jun 17 |
| Tomatoes | Transplant outdoors | May 28 – Jun 10 |
| Peppers | Start seeds indoors | Apr 11 – May 12 |
| Peppers | Transplant outdoors | Jun 11 – Jul 12 |
| Eggplant | Start seeds indoors | Apr 28 – May 27 |
| Eggplant | Transplant outdoors | Jun 11 – Jul 12 |
| Cucumbers | Sow outdoors | Jun 11 – Jun 20 |
| Summer squash | Sow outdoors | May 28 – Jul 12 |
| Winter squash & pumpkins | Sow outdoors | Jun 11 – Jul 12 |
| Snap beans | Sow outdoors | May 28 – Jul 13 |
| Sweet corn | Sow outdoors | May 28 – Jun 10 |
| Watermelon & cantaloupe | Sow outdoors | Jun 11 – Jul 12 |
| Okra | Sow outdoors | Jun 4 – Jun 27 |
| Peas | Sow outdoors (spring) | Apr 11 – May 27 |
| Potatoes | Plant outdoors (spring) | Apr 11 – Jun 11 |
| Onions | Start seeds indoors (spring) | Feb 28 – Mar 27 |
| Onions | Transplant outdoors (spring) | Apr 28 – May 27 |
| Broccoli | Start seeds indoors (spring) | Mar 24 – Apr 27 |
| Broccoli | Transplant outdoors (spring) | Apr 28 – May 27 |
| Broccoli | Start seeds indoors (fall) | May 31 – Jun 10 |
| Broccoli | Transplant outdoors (fall) | Jun 30 – Jul 11 |
| Cabbage | Start seeds indoors (spring) | Mar 14 – Apr 11 |
| Cabbage | Transplant outdoors (spring) | Apr 11 – May 12 |
| Cabbage | Start seeds indoors (fall) | May 21 – Jun 20 |
| Cabbage | Transplant outdoors (fall) | Jun 20 – Jul 21 |
| Leaf lettuce | Sow outdoors (spring) | Apr 11 – Jun 27 |
| Leaf lettuce | Sow outdoors (fall) | Jun 20 – Aug 6 |
| Spinach | Sow outdoors (spring) | Apr 4 – May 18 |
| Spinach | Sow outdoors (fall) | Jul 7 – Aug 11 |
| Radishes | Sow outdoors (spring) | Apr 11 – Jun 1 |
| Radishes | Sow outdoors (fall) | Jun 20 – Aug 21 |
| Kale | Sow outdoors (spring) | Apr 28 – May 18 |
| Kale | Sow outdoors (fall) | Jun 13 – Jul 21 |
| Carrots | Sow outdoors (spring) | May 12 – Jun 27 |
| Carrots | Sow outdoors (fall) | May 21 – Jul 6 |
| Garlic | Plant outdoors (fall) | Sep 20 – Oct 21 |
Where these dates come from
ZIP code 83802 is matched to the NOAA station Mullan, ID, 22 km away, at 3,201 ft elevation (647 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Mullan, ID (used) | 3,201 ft | May 12 | Sep 30 |
| Wallace, ID | 2,710 ft | May 5 | Oct 2 |
| Mullan Pass Vor/Dme, ID | 6,028 ft | Jun 10 | Sep 23 |
| Kellogg, ID | 2,377 ft | May 14 | Sep 26 |
Frost dates near Avery
- Calder, ID 83808 · last May 12, first Sep 30
- Mullan, ID 83846 · last May 12, first Sep 30
- Wallace, ID 83873 · last May 5, first Oct 2
- Silverton, ID 83867 · last May 5, first Oct 2
- Osburn, ID 83849 · last May 5, first Oct 2
- Saltese, MT 59867 · last —, first —
- Kellogg, ID 83837 · last May 14, first Sep 26
- Haugan, MT 59842 · last —, first —
Frequently asked questions
- When is the last frost in Avery, ID?
- For ZIP code 83802, the average last spring frost (32°F) is May 12, based on NOAA 1991-2020 climate normals for the Mullan, ID weather station. There is a 1-in-10 chance of a frost after June 19.
- When is the first frost in Avery, ID?
- The average first fall frost (32°F) is September 30. There is a 1-in-10 chance of frost by September 12, so tender plants are at risk from that point on.
- How long is the growing season in 83802?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 138 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.