Frost dates for 97480Swisshome, OR
The average last spring frost in Swisshome is April 18 and the average first fall frost is October 25, giving a typical growing season of about 189 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 18
- Average first fall frost
- Oct 25
- Growing season
- 189 days
Safer after May 5 (1-in-10 risk)
Possible by Oct 6 (1-in-10 risk)
Last frost typically in 168 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 21 · May 5 · May 24 | Sep 20 · Oct 6 · Oct 26 | 153 days | 100% |
| Frost / freeze (32°F) | Mar 25 · Apr 18 · May 5 | Oct 6 · Oct 25 · Nov 12 | 189 days | 100% |
| Hard freeze (28°F) | Feb 16 · Mar 16 · Apr 16 | Oct 22 · Nov 11 · Dec 5 | 239 days | 100% |
Planting calendar for Swisshome
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 | Mar 18 – May 24 |
| Tomatoes | Transplant outdoors | May 4 – Jul 5 |
| Peppers | Start seeds indoors | Mar 18 – Apr 18 |
| Peppers | Transplant outdoors | May 18 – Jun 18 |
| Eggplant | Start seeds indoors | Apr 4 – May 3 |
| Eggplant | Transplant outdoors | May 18 – Jun 18 |
| Cucumbers | Sow outdoors | May 18 – Jul 15 |
| Summer squash | Sow outdoors | May 4 – Jun 18 |
| Winter squash & pumpkins | Sow outdoors | May 18 – Jun 18 |
| Snap beans | Sow outdoors | May 4 – Aug 7 |
| Sweet corn | Sow outdoors | May 4 – Jul 5 |
| Watermelon & cantaloupe | Sow outdoors | May 18 – Jun 18 |
| Okra | Sow outdoors | May 11 – Jun 3 |
| Peas | Sow outdoors (spring) | Mar 18 – May 3 |
| Potatoes | Plant outdoors (spring) | Mar 18 – May 18 |
| Onions | Start seeds indoors (spring) | Feb 4 – Mar 3 |
| Onions | Transplant outdoors (spring) | Apr 4 – May 3 |
| Broccoli | Start seeds indoors (spring) | Feb 28 – Apr 3 |
| Broccoli | Transplant outdoors (spring) | Apr 4 – May 3 |
| Broccoli | Start seeds indoors (fall) | Jun 25 – Jul 5 |
| Broccoli | Transplant outdoors (fall) | Jul 25 – Aug 5 |
| Cabbage | Start seeds indoors (spring) | Feb 18 – Mar 18 |
| Cabbage | Transplant outdoors (spring) | Mar 18 – Apr 18 |
| Cabbage | Start seeds indoors (fall) | Jun 15 – Jul 15 |
| Cabbage | Transplant outdoors (fall) | Jul 15 – Aug 15 |
| Leaf lettuce | Sow outdoors (spring) | Mar 18 – Jun 3 |
| Leaf lettuce | Sow outdoors (fall) | Jul 15 – Aug 31 |
| Spinach | Sow outdoors (spring) | Mar 11 – Apr 24 |
| Spinach | Sow outdoors (fall) | Aug 1 – Sep 5 |
| Radishes | Sow outdoors (spring) | Mar 18 – May 8 |
| Radishes | Sow outdoors (fall) | Jul 15 – Sep 15 |
| Kale | Sow outdoors (spring) | Apr 4 – Apr 24 |
| Kale | Sow outdoors (fall) | Jul 8 – Aug 15 |
| Carrots | Sow outdoors (spring) | Apr 18 – Jun 3 |
| Carrots | Sow outdoors (fall) | Jun 15 – Jul 31 |
| Garlic | Plant outdoors (fall) | Oct 15 – Nov 15 |
Where these dates come from
ZIP code 97480 is matched to the NOAA station Fern Ridge-Veneta, OR, 36.8 km away, at 485 ft elevation (460 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Fern Ridge-Veneta, OR (used) | 485 ft | Apr 18 | Oct 25 |
| Mapleton, OR | 17 ft | Feb 15 | Dec 9 |
| Florence #2, OR | 75 ft | Apr 10 | Nov 15 |
| Honeyman Sp, OR | 115 ft | Mar 28 | Nov 22 |
Frost dates near Swisshome
- Mapleton, OR 97453 · last Feb 15, first Dec 9
- Deadwood, OR 97430 · last Apr 18, first Oct 25
- Walton, OR 97490 · last Apr 18, first Oct 25
- Florence, OR 97439 · last Mar 28, first Nov 22
- Westlake, OR 97493 · last Mar 28, first Nov 22
- Blachly, OR 97412 · last Apr 18, first Oct 25
- Noti, OR 97461 · last Apr 18, first Oct 25
- Yachats, OR 97498 · last Feb 19, first Dec 11
Frequently asked questions
- When is the last frost in Swisshome, OR?
- For ZIP code 97480, the average last spring frost (32°F) is April 18, based on NOAA 1991-2020 climate normals for the Fern Ridge-Veneta, OR weather station. There is a 1-in-10 chance of a frost after May 5.
- When is the first frost in Swisshome, OR?
- The average first fall frost (32°F) is October 25. There is a 1-in-10 chance of frost by October 6, so tender plants are at risk from that point on.
- How long is the growing season in 97480?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 189 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.