Frost dates for 83338Jerome, ID
The average last spring frost in Jerome is May 2 and the average first fall frost is October 14, giving a typical growing season of about 166 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 2
- Average first fall frost
- Oct 14
- Growing season
- 166 days
Safer after May 30 (1-in-10 risk)
Possible by Sep 30 (1-in-10 risk)
Last frost typically in 186 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) | Apr 30 · May 15 · Jun 8 | Sep 17 · Oct 3 · Oct 17 | 138 days | 100% |
| Frost / freeze (32°F) | Apr 15 · May 2 · May 30 | Sep 30 · Oct 14 · Oct 29 | 166 days | 100% |
| Hard freeze (28°F) | Mar 24 · Apr 14 · May 10 | Oct 13 · Oct 27 · Nov 11 | 194 days | 100% |
Planting calendar for Jerome
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 1 – Jun 7 |
| Tomatoes | Transplant outdoors | May 18 – Jun 24 |
| Peppers | Start seeds indoors | Apr 1 – May 2 |
| Peppers | Transplant outdoors | Jun 1 – Jul 2 |
| Eggplant | Start seeds indoors | Apr 18 – May 17 |
| Eggplant | Transplant outdoors | Jun 1 – Jul 2 |
| Cucumbers | Sow outdoors | Jun 1 – Jul 4 |
| Summer squash | Sow outdoors | May 18 – Jul 2 |
| Winter squash & pumpkins | Sow outdoors | Jun 1 – Jul 2 |
| Snap beans | Sow outdoors | May 18 – Jul 27 |
| Sweet corn | Sow outdoors | May 18 – Jun 24 |
| Watermelon & cantaloupe | Sow outdoors | Jun 1 – Jul 2 |
| Okra | Sow outdoors | May 25 – Jun 17 |
| Peas | Sow outdoors (spring) | Apr 1 – May 17 |
| Potatoes | Plant outdoors (spring) | Apr 1 – Jun 1 |
| Onions | Start seeds indoors (spring) | Feb 18 – Mar 17 |
| Onions | Transplant outdoors (spring) | Apr 18 – May 17 |
| Broccoli | Start seeds indoors (spring) | Mar 14 – Apr 17 |
| Broccoli | Transplant outdoors (spring) | Apr 18 – May 17 |
| Broccoli | Start seeds indoors (fall) | Jun 14 – Jun 24 |
| Broccoli | Transplant outdoors (fall) | Jul 14 – Jul 25 |
| Cabbage | Start seeds indoors (spring) | Mar 4 – Apr 1 |
| Cabbage | Transplant outdoors (spring) | Apr 1 – May 2 |
| Cabbage | Start seeds indoors (fall) | Jun 4 – Jul 4 |
| Cabbage | Transplant outdoors (fall) | Jul 4 – Aug 4 |
| Leaf lettuce | Sow outdoors (spring) | Apr 1 – Jun 17 |
| Leaf lettuce | Sow outdoors (fall) | Jul 4 – Aug 20 |
| Spinach | Sow outdoors (spring) | Mar 25 – May 8 |
| Spinach | Sow outdoors (fall) | Jul 21 – Aug 25 |
| Radishes | Sow outdoors (spring) | Apr 1 – May 22 |
| Radishes | Sow outdoors (fall) | Jul 4 – Sep 4 |
| Kale | Sow outdoors (spring) | Apr 18 – May 8 |
| Kale | Sow outdoors (fall) | Jun 27 – Aug 4 |
| Carrots | Sow outdoors (spring) | May 2 – Jun 17 |
| Carrots | Sow outdoors (fall) | Jun 4 – Jul 20 |
| Garlic | Plant outdoors (fall) | Oct 4 – Nov 4 |
Where these dates come from
ZIP code 83338 is matched to the NOAA station Jerome, ID, 2.2 km away, at 3,740 ft elevation (95 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Jerome, ID (used) | 3,740 ft | May 2 | Oct 14 |
| Jerome Co Ap, ID | 4,048 ft | May 1 | Oct 14 |
| Twin Falls-Kmvt, ID | 3,670 ft | Apr 30 | Oct 9 |
| Twin Falls 6 E, ID | 3,960 ft | May 6 | Oct 3 |
Frost dates near Jerome
- Twin Falls, ID 83303 · last Apr 30, first Oct 9
- Wendell, ID 83355 · last May 2, first Oct 14
- Filer, ID 83328 · last Apr 25, first Oct 15
- Kimberly, ID 83341 · last May 6, first Oct 3
- Eden, ID 83325 · last May 7, first Oct 5
- Buhl, ID 83316 · last Apr 25, first Oct 15
- Hansen, ID 83334 · last May 6, first Oct 3
- Shoshone, ID 83352 · last Apr 24, first Oct 16
Frequently asked questions
- When is the last frost in Jerome, ID?
- For ZIP code 83338, the average last spring frost (32°F) is May 2, based on NOAA 1991-2020 climate normals for the Jerome, ID weather station. There is a 1-in-10 chance of a frost after May 30.
- When is the first frost in Jerome, ID?
- The average first fall frost (32°F) is October 14. There is a 1-in-10 chance of frost by September 30, so tender plants are at risk from that point on.
- How long is the growing season in 83338?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 166 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.