Frost dates for 98352Sumner, WA
The average last spring frost in Sumner is April 11 and the average first fall frost is October 30, giving a typical growing season of about 202 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 11
- Average first fall frost
- Oct 30
- Growing season
- 202 days
Safer after Apr 29 (1-in-10 risk)
Possible by Oct 13 (1-in-10 risk)
First frost typically in 0 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 1 · May 17 | Sep 30 · Oct 12 · Oct 31 | 163 days | 100% |
| Frost / freeze (32°F) | Mar 23 · Apr 11 · Apr 29 | Oct 13 · Oct 30 · Nov 17 | 202 days | 100% |
| Hard freeze (28°F) | Feb 19 · Mar 16 · Apr 8 | Oct 28 · Nov 14 · Dec 8 | 244 days | 100% |
Planting calendar for Sumner
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 11 – May 17 |
| Tomatoes | Transplant outdoors | Apr 27 – Jul 10 |
| Peppers | Start seeds indoors | Mar 11 – Apr 11 |
| Peppers | Transplant outdoors | May 11 – Jun 11 |
| Eggplant | Start seeds indoors | Mar 28 – Apr 26 |
| Eggplant | Transplant outdoors | May 11 – Jun 11 |
| Cucumbers | Sow outdoors | May 11 – Jul 20 |
| Summer squash | Sow outdoors | Apr 27 – Jun 11 |
| Winter squash & pumpkins | Sow outdoors | May 11 – Jun 11 |
| Snap beans | Sow outdoors | Apr 27 – Aug 12 |
| Sweet corn | Sow outdoors | Apr 27 – Jul 10 |
| Watermelon & cantaloupe | Sow outdoors | May 11 – Jun 11 |
| Okra | Sow outdoors | May 4 – May 27 |
| Peas | Sow outdoors (spring) | Mar 11 – Apr 26 |
| Potatoes | Plant outdoors (spring) | Mar 11 – May 11 |
| Onions | Start seeds indoors (spring) | Jan 28 – Feb 24 |
| Onions | Transplant outdoors (spring) | Mar 28 – Apr 26 |
| Broccoli | Start seeds indoors (spring) | Feb 21 – Mar 27 |
| Broccoli | Transplant outdoors (spring) | Mar 28 – Apr 26 |
| Broccoli | Start seeds indoors (fall) | Jun 30 – Jul 10 |
| Broccoli | Transplant outdoors (fall) | Jul 30 – Aug 10 |
| Cabbage | Start seeds indoors (spring) | Feb 11 – Mar 11 |
| Cabbage | Transplant outdoors (spring) | Mar 11 – Apr 11 |
| Cabbage | Start seeds indoors (fall) | Jun 20 – Jul 20 |
| Cabbage | Transplant outdoors (fall) | Jul 20 – Aug 20 |
| Leaf lettuce | Sow outdoors (spring) | Mar 11 – May 27 |
| Leaf lettuce | Sow outdoors (fall) | Jul 20 – Sep 5 |
| Spinach | Sow outdoors (spring) | Mar 4 – Apr 17 |
| Spinach | Sow outdoors (fall) | Aug 6 – Sep 10 |
| Radishes | Sow outdoors (spring) | Mar 11 – May 1 |
| Radishes | Sow outdoors (fall) | Jul 20 – Sep 20 |
| Kale | Sow outdoors (spring) | Mar 28 – Apr 17 |
| Kale | Sow outdoors (fall) | Jul 13 – Aug 20 |
| Carrots | Sow outdoors (spring) | Apr 11 – May 27 |
| Carrots | Sow outdoors (fall) | Jun 20 – Aug 5 |
| Garlic | Plant outdoors (fall) | Oct 20 – Nov 20 |
Where these dates come from
ZIP code 98352 is matched to the NOAA station Mcmillin Rsvr, WA, 13.3 km away, at 579 ft elevation (284 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Mcmillin Rsvr, WA (used) | 579 ft | Apr 11 | Oct 30 |
| Buckley 1 Ne, WA | 685 ft | Apr 7 | Oct 30 |
| Mud Mtn Dam, WA | 1,308 ft | Apr 18 | Oct 31 |
| Tacoma #1, WA | 25 ft | Mar 8 | Nov 14 |
Frost dates near Sumner
- Paradise Inn, WA 98398 · last Apr 11, first Oct 30
- Camp Murray, WA 98430 · last Apr 11, first Oct 30
- Carbonado, WA 98323 · last Apr 18, first Oct 31
- Orting, WA 98360 · last Apr 11, first Oct 30
- Wilkeson, WA 98396 · last Apr 18, first Oct 31
- South Prairie, WA 98385 · last Apr 11, first Oct 30
- Bonney Lake, WA 98391 · last Apr 11, first Oct 30
- Buckley, WA 98321 · last Apr 11, first Oct 30
Frequently asked questions
- When is the last frost in Sumner, WA?
- For ZIP code 98352, the average last spring frost (32°F) is April 11, based on NOAA 1991-2020 climate normals for the Mcmillin Rsvr, WA weather station. There is a 1-in-10 chance of a frost after April 29.
- When is the first frost in Sumner, WA?
- The average first fall frost (32°F) is October 30. There is a 1-in-10 chance of frost by October 13, so tender plants are at risk from that point on.
- How long is the growing season in 98352?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 202 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.