Frost dates for 98826Leavenworth, WA
The average last spring frost in Leavenworth is May 22 and the average first fall frost is September 22, giving a typical growing season of about 121 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 22
- Average first fall frost
- Sep 22
- Growing season
- 121 days
Safer after Jun 13 (1-in-10 risk)
Possible by Sep 7 (1-in-10 risk)
Last frost typically in 208 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 24 · Jun 13 · Jul 1 | Aug 24 · Sep 8 · Sep 21 | 85 days | 100% |
| Frost / freeze (32°F) | May 2 · May 22 · Jun 13 | Sep 7 · Sep 22 · Oct 4 | 121 days | 100% |
| Hard freeze (28°F) | Apr 19 · May 3 · May 20 | Sep 22 · Oct 4 · Oct 20 | 153 days | 100% |
Planting calendar for Leavenworth
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 21 – Jun 27 |
| Tomatoes | Transplant outdoors | Jun 7 – Jun 2 |
| Peppers | Start seeds indoors | Apr 21 – May 22 |
| Peppers | Transplant outdoors | Jun 21 – Jul 22 |
| Eggplant | Start seeds indoors | May 8 – Jun 6 |
| Eggplant | Transplant outdoors | Jun 21 – Jul 22 |
| Cucumbers | Sow outdoors | Jun 21 – Jun 12 |
| Summer squash | Sow outdoors | Jun 7 – Jul 22 |
| Winter squash & pumpkins | Sow outdoors | Jun 21 – Jul 22 |
| Snap beans | Sow outdoors | Jun 7 – Jul 5 |
| Sweet corn | Sow outdoors | Jun 7 – Jun 2 |
| Watermelon & cantaloupe | Sow outdoors | Jun 21 – Jul 22 |
| Okra | Sow outdoors | Jun 14 – Jul 7 |
| Peas | Sow outdoors (spring) | Apr 21 – Jun 6 |
| Potatoes | Plant outdoors (spring) | Apr 21 – Jun 21 |
| Onions | Start seeds indoors (spring) | Mar 10 – Apr 6 |
| Onions | Transplant outdoors (spring) | May 8 – Jun 6 |
| Broccoli | Start seeds indoors (spring) | Apr 3 – May 7 |
| Broccoli | Transplant outdoors (spring) | May 8 – Jun 6 |
| Broccoli | Start seeds indoors (fall) | May 23 – Jun 2 |
| Broccoli | Transplant outdoors (fall) | Jun 22 – Jul 3 |
| Cabbage | Start seeds indoors (spring) | Mar 24 – Apr 21 |
| Cabbage | Transplant outdoors (spring) | Apr 21 – May 22 |
| Cabbage | Start seeds indoors (fall) | May 13 – Jun 12 |
| Cabbage | Transplant outdoors (fall) | Jun 12 – Jul 13 |
| Leaf lettuce | Sow outdoors (spring) | Apr 21 – Jul 7 |
| Leaf lettuce | Sow outdoors (fall) | Jun 12 – Jul 29 |
| Spinach | Sow outdoors (spring) | Apr 14 – May 28 |
| Spinach | Sow outdoors (fall) | Jun 29 – Aug 3 |
| Radishes | Sow outdoors (spring) | Apr 21 – Jun 11 |
| Radishes | Sow outdoors (fall) | Jun 12 – Aug 13 |
| Kale | Sow outdoors (spring) | May 8 – May 28 |
| Kale | Sow outdoors (fall) | Jun 5 – Jul 13 |
| Carrots | Sow outdoors (spring) | May 22 – Jul 7 |
| Carrots | Sow outdoors (fall) | May 13 – Jun 28 |
| Garlic | Plant outdoors (fall) | Sep 12 – Oct 13 |
Where these dates come from
ZIP code 98826 is matched to the NOAA station Plain, WA, 15.9 km away, at 1,936 ft elevation (46 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Plain, WA (used) | 1,936 ft | May 22 | Sep 22 |
| Leavenworth 3 S, WA | 1,128 ft | May 10 | Sep 30 |
| Entiat Fish Hatchery, WA | 1,027 ft | Apr 5 | Oct 24 |
| Wenatchee, WA | 626 ft | Apr 4 | Oct 28 |
Frost dates near Leavenworth
- Peshastin, WA 98847 · last May 10, first Sep 30
- Dryden, WA 98821 · last May 10, first Sep 30
- Cashmere, WA 98815 · last May 10, first Sep 30
- Ardenvoir, WA 98811 · last Apr 5, first Oct 24
- Monitor, WA 98836 · last Apr 4, first Oct 28
- Entiat, WA 98822 · last May 14, first Oct 1
- Wenatchee, WA 98801 · last Apr 4, first Oct 28
- Orondo, WA 98843 · last May 22, first Sep 22
Frequently asked questions
- When is the last frost in Leavenworth, WA?
- For ZIP code 98826, the average last spring frost (32°F) is May 22, based on NOAA 1991-2020 climate normals for the Plain, WA weather station. There is a 1-in-10 chance of a frost after June 13.
- When is the first frost in Leavenworth, WA?
- The average first fall frost (32°F) is September 22. There is a 1-in-10 chance of frost by September 7, so tender plants are at risk from that point on.
- How long is the growing season in 98826?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 121 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.