Frost dates for 83610Cambridge, ID
The average last spring frost in Cambridge is May 15 and the average first fall frost is September 27, giving a typical growing season of about 134 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 15
- Average first fall frost
- Sep 27
- Growing season
- 134 days
Safer after Jun 4 (1-in-10 risk)
Possible by Sep 12 (1-in-10 risk)
Last frost typically in 194 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 15 · Jun 3 · Jun 21 | Sep 2 · Sep 16 · Sep 30 | 104 days | 100% |
| Frost / freeze (32°F) | Apr 29 · May 15 · Jun 4 | Sep 12 · Sep 27 · Oct 9 | 134 days | 100% |
| Hard freeze (28°F) | Apr 8 · Apr 28 · May 15 | Sep 23 · Oct 7 · Oct 22 | 164 days | 100% |
Planting calendar for Cambridge
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 14 – Jun 20 |
| Tomatoes | Transplant outdoors | May 31 – Jun 7 |
| Peppers | Start seeds indoors | Apr 14 – May 15 |
| Peppers | Transplant outdoors | Jun 14 – Jul 15 |
| Eggplant | Start seeds indoors | May 1 – May 30 |
| Eggplant | Transplant outdoors | Jun 14 – Jul 15 |
| Cucumbers | Sow outdoors | Jun 14 – Jun 17 |
| Summer squash | Sow outdoors | May 31 – Jul 15 |
| Winter squash & pumpkins | Sow outdoors | Jun 14 – Jul 15 |
| Snap beans | Sow outdoors | May 31 – Jul 10 |
| Sweet corn | Sow outdoors | May 31 – Jun 7 |
| Watermelon & cantaloupe | Sow outdoors | Jun 14 – Jul 15 |
| Okra | Sow outdoors | Jun 7 – Jun 30 |
| Peas | Sow outdoors (spring) | Apr 14 – May 30 |
| Potatoes | Plant outdoors (spring) | Apr 14 – Jun 14 |
| Onions | Start seeds indoors (spring) | Mar 3 – Mar 30 |
| Onions | Transplant outdoors (spring) | May 1 – May 30 |
| Broccoli | Start seeds indoors (spring) | Mar 27 – Apr 30 |
| Broccoli | Transplant outdoors (spring) | May 1 – May 30 |
| Broccoli | Start seeds indoors (fall) | May 28 – Jun 7 |
| Broccoli | Transplant outdoors (fall) | Jun 27 – Jul 8 |
| Cabbage | Start seeds indoors (spring) | Mar 17 – Apr 14 |
| Cabbage | Transplant outdoors (spring) | Apr 14 – May 15 |
| Cabbage | Start seeds indoors (fall) | May 18 – Jun 17 |
| Cabbage | Transplant outdoors (fall) | Jun 17 – Jul 18 |
| Leaf lettuce | Sow outdoors (spring) | Apr 14 – Jun 30 |
| Leaf lettuce | Sow outdoors (fall) | Jun 17 – Aug 3 |
| Spinach | Sow outdoors (spring) | Apr 7 – May 21 |
| Spinach | Sow outdoors (fall) | Jul 4 – Aug 8 |
| Radishes | Sow outdoors (spring) | Apr 14 – Jun 4 |
| Radishes | Sow outdoors (fall) | Jun 17 – Aug 18 |
| Kale | Sow outdoors (spring) | May 1 – May 21 |
| Kale | Sow outdoors (fall) | Jun 10 – Jul 18 |
| Carrots | Sow outdoors (spring) | May 15 – Jun 30 |
| Carrots | Sow outdoors (fall) | May 18 – Jul 3 |
| Garlic | Plant outdoors (fall) | Sep 17 – Oct 18 |
Where these dates come from
ZIP code 83610 is matched to the NOAA station Cambridge, ID, 2.1 km away, at 2,650 ft elevation (224 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Cambridge, ID (used) | 2,650 ft | May 15 | Sep 27 |
| Council, ID | 2,943 ft | May 10 | Oct 2 |
| Brownlee Dam, ID | 1,844 ft | Apr 2 | Nov 5 |
| Richland, OR | 2,215 ft | May 10 | Oct 1 |
Frost dates near Cambridge
- Midvale, ID 83645 · last May 15, first Sep 27
- Mesa, ID 83643 · last May 10, first Oct 2
- Indian Valley, ID 83632 · last May 15, first Sep 27
- Council, ID 83612 · last May 10, first Oct 2
- Weiser, ID 83672 · last Apr 23, first Oct 13
- Oxbow, OR 97840 · last Apr 2, first Nov 5
- Halfway, OR 97834 · last May 15, first Sep 24
- Ola, ID 83657 · last May 31, first Sep 16
Frequently asked questions
- When is the last frost in Cambridge, ID?
- For ZIP code 83610, the average last spring frost (32°F) is May 15, based on NOAA 1991-2020 climate normals for the Cambridge, ID weather station. There is a 1-in-10 chance of a frost after June 4.
- When is the first frost in Cambridge, ID?
- The average first fall frost (32°F) is September 27. 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 83610?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 134 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.