Frost dates for 97386Sweet Home, OR
The average last spring frost in Sweet Home is April 12 and the average first fall frost is October 28, giving a typical growing season of about 197 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 12
- Average first fall frost
- Oct 28
- Growing season
- 197 days
Safer after May 5 (1-in-10 risk)
Possible by Oct 5 (1-in-10 risk)
Last frost typically in 162 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 17 · May 6 · May 25 | Sep 14 · Oct 6 · Oct 27 | 153 days | 100% |
| Frost / freeze (32°F) | Mar 16 · Apr 12 · May 5 | Oct 5 · Oct 28 · Nov 21 | 197 days | 100% |
| Hard freeze (28°F) | Feb 12 · Mar 9 · Apr 11 | Oct 25 · Nov 18 · Dec 16 | 252 days | 100% |
Planting calendar for Sweet Home
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 12 – May 18 |
| Tomatoes | Transplant outdoors | Apr 28 – Jul 8 |
| Peppers | Start seeds indoors | Mar 12 – Apr 12 |
| Peppers | Transplant outdoors | May 12 – Jun 12 |
| Eggplant | Start seeds indoors | Mar 29 – Apr 27 |
| Eggplant | Transplant outdoors | May 12 – Jun 12 |
| Cucumbers | Sow outdoors | May 12 – Jul 18 |
| Summer squash | Sow outdoors | Apr 28 – Jun 12 |
| Winter squash & pumpkins | Sow outdoors | May 12 – Jun 12 |
| Snap beans | Sow outdoors | Apr 28 – Aug 10 |
| Sweet corn | Sow outdoors | Apr 28 – Jul 8 |
| Watermelon & cantaloupe | Sow outdoors | May 12 – Jun 12 |
| Okra | Sow outdoors | May 5 – May 28 |
| Peas | Sow outdoors (spring) | Mar 12 – Apr 27 |
| Potatoes | Plant outdoors (spring) | Mar 12 – May 12 |
| Onions | Start seeds indoors (spring) | Jan 29 – Feb 25 |
| Onions | Transplant outdoors (spring) | Mar 29 – Apr 27 |
| Broccoli | Start seeds indoors (spring) | Feb 22 – Mar 28 |
| Broccoli | Transplant outdoors (spring) | Mar 29 – Apr 27 |
| Broccoli | Start seeds indoors (fall) | Jun 28 – Jul 8 |
| Broccoli | Transplant outdoors (fall) | Jul 28 – Aug 8 |
| Cabbage | Start seeds indoors (spring) | Feb 12 – Mar 12 |
| Cabbage | Transplant outdoors (spring) | Mar 12 – Apr 12 |
| Cabbage | Start seeds indoors (fall) | Jun 18 – Jul 18 |
| Cabbage | Transplant outdoors (fall) | Jul 18 – Aug 18 |
| Leaf lettuce | Sow outdoors (spring) | Mar 12 – May 28 |
| Leaf lettuce | Sow outdoors (fall) | Jul 18 – Sep 3 |
| Spinach | Sow outdoors (spring) | Mar 5 – Apr 18 |
| Spinach | Sow outdoors (fall) | Aug 4 – Sep 8 |
| Radishes | Sow outdoors (spring) | Mar 12 – May 2 |
| Radishes | Sow outdoors (fall) | Jul 18 – Sep 18 |
| Kale | Sow outdoors (spring) | Mar 29 – Apr 18 |
| Kale | Sow outdoors (fall) | Jul 11 – Aug 18 |
| Carrots | Sow outdoors (spring) | Apr 12 – May 28 |
| Carrots | Sow outdoors (fall) | Jun 18 – Aug 3 |
| Garlic | Plant outdoors (fall) | Oct 18 – Nov 18 |
Where these dates come from
ZIP code 97386 is matched to the NOAA station Foster Dam, OR, 4.8 km away, at 550 ft elevation (9 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Foster Dam, OR (used) | 550 ft | Apr 12 | Oct 28 |
| Cascadia, OR | 960 ft | Apr 29 | Oct 13 |
| Lebanon, OR | 330 ft | Mar 14 | Nov 18 |
| Lacomb 3 Nne, OR | 520 ft | Apr 26 | Oct 24 |
Frost dates near Sweet Home
- Crawfordsville, OR 97336 · last Apr 12, first Oct 28
- Foster, OR 97345 · last Apr 29, first Oct 13
- Brownsville, OR 97327 · last Apr 12, first Oct 28
- Lebanon, OR 97355 · last Apr 26, first Oct 24
- Cascadia, OR 97329 · last Apr 29, first Oct 13
- Marcola, OR 97454 · last Apr 3, first Nov 11
- Crabtree, OR 97335 · last Apr 26, first Oct 24
- Shedd, OR 97377 · last Apr 17, first Oct 28
Frequently asked questions
- When is the last frost in Sweet Home, OR?
- For ZIP code 97386, the average last spring frost (32°F) is April 12, based on NOAA 1991-2020 climate normals for the Foster Dam, OR weather station. There is a 1-in-10 chance of a frost after May 5.
- When is the first frost in Sweet Home, OR?
- The average first fall frost (32°F) is October 28. There is a 1-in-10 chance of frost by October 5, so tender plants are at risk from that point on.
- How long is the growing season in 97386?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 197 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.