Frost dates for 99322Bickleton, WA
The average last spring frost in Bickleton is May 16 and the average first fall frost is October 9, giving a typical growing season of about 144 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 16
- Average first fall frost
- Oct 9
- Growing season
- 144 days
Safer after Jun 10 (1-in-10 risk)
Possible by Sep 26 (1-in-10 risk)
Last frost typically in 196 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 17 · Jun 9 · Jun 29 | Sep 7 · Sep 29 · Oct 12 | 109 days | 100% |
| Frost / freeze (32°F) | Apr 28 · May 16 · Jun 10 | Sep 26 · Oct 9 · Oct 26 | 144 days | 100% |
| Hard freeze (28°F) | Apr 7 · Apr 27 · May 16 | Oct 6 · Oct 22 · Nov 8 | 177 days | 100% |
Planting calendar for Bickleton
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 15 – Jun 21 |
| Tomatoes | Transplant outdoors | Jun 1 – Jun 19 |
| Peppers | Start seeds indoors | Apr 15 – May 16 |
| Peppers | Transplant outdoors | Jun 15 – Jul 16 |
| Eggplant | Start seeds indoors | May 2 – May 31 |
| Eggplant | Transplant outdoors | Jun 15 – Jul 16 |
| Cucumbers | Sow outdoors | Jun 15 – Jun 29 |
| Summer squash | Sow outdoors | Jun 1 – Jul 16 |
| Winter squash & pumpkins | Sow outdoors | Jun 15 – Jul 16 |
| Snap beans | Sow outdoors | Jun 1 – Jul 22 |
| Sweet corn | Sow outdoors | Jun 1 – Jun 19 |
| Watermelon & cantaloupe | Sow outdoors | Jun 15 – Jul 16 |
| Okra | Sow outdoors | Jun 8 – Jul 1 |
| Peas | Sow outdoors (spring) | Apr 15 – May 31 |
| Potatoes | Plant outdoors (spring) | Apr 15 – Jun 15 |
| Onions | Start seeds indoors (spring) | Mar 4 – Mar 31 |
| Onions | Transplant outdoors (spring) | May 2 – May 31 |
| Broccoli | Start seeds indoors (spring) | Mar 28 – May 1 |
| Broccoli | Transplant outdoors (spring) | May 2 – May 31 |
| Broccoli | Start seeds indoors (fall) | Jun 9 – Jun 19 |
| Broccoli | Transplant outdoors (fall) | Jul 9 – Jul 20 |
| Cabbage | Start seeds indoors (spring) | Mar 18 – Apr 15 |
| Cabbage | Transplant outdoors (spring) | Apr 15 – May 16 |
| Cabbage | Start seeds indoors (fall) | May 30 – Jun 29 |
| Cabbage | Transplant outdoors (fall) | Jun 29 – Jul 30 |
| Leaf lettuce | Sow outdoors (spring) | Apr 15 – Jul 1 |
| Leaf lettuce | Sow outdoors (fall) | Jun 29 – Aug 15 |
| Spinach | Sow outdoors (spring) | Apr 8 – May 22 |
| Spinach | Sow outdoors (fall) | Jul 16 – Aug 20 |
| Radishes | Sow outdoors (spring) | Apr 15 – Jun 5 |
| Radishes | Sow outdoors (fall) | Jun 29 – Aug 30 |
| Kale | Sow outdoors (spring) | May 2 – May 22 |
| Kale | Sow outdoors (fall) | Jun 22 – Jul 30 |
| Carrots | Sow outdoors (spring) | May 16 – Jul 1 |
| Carrots | Sow outdoors (fall) | May 30 – Jul 15 |
| Garlic | Plant outdoors (fall) | Sep 29 – Oct 30 |
Where these dates come from
ZIP code 99322 is matched to the NOAA station Bickleton, WA, 15.8 km away, at 3,015 ft elevation (938 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Bickleton, WA (used) | 3,015 ft | May 16 | Oct 9 |
| Arlington, OR | 277 ft | Apr 6 | Oct 21 |
| Boardman, OR | 280 ft | Apr 14 | Oct 21 |
| Prosser, WA | 830 ft | Apr 14 | Oct 22 |
Frost dates near Bickleton
- Roosevelt, WA 99356 · last Jun 2, first Oct 1
- Paterson, WA 99345 · last Apr 14, first Oct 21
- Mabton, WA 98935 · last May 1, first Oct 6
- Boardman, OR 97818 · last Apr 14, first Oct 21
- Arlington, OR 97812 · last Apr 6, first Oct 21
- Grandview, WA 98930 · last May 1, first Oct 6
- Prosser, WA 99350 · last Apr 14, first Oct 22
- Sunnyside, WA 98944 · last May 1, first Oct 6
Frequently asked questions
- When is the last frost in Bickleton, WA?
- For ZIP code 99322, the average last spring frost (32°F) is May 16, based on NOAA 1991-2020 climate normals for the Bickleton, WA weather station. There is a 1-in-10 chance of a frost after June 10.
- When is the first frost in Bickleton, WA?
- The average first fall frost (32°F) is October 9. There is a 1-in-10 chance of frost by September 26, so tender plants are at risk from that point on.
- How long is the growing season in 99322?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 144 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.