Frost dates for 99645Palmer, AK
The average last spring frost in Palmer is May 22 and the average first fall frost is September 16, giving a typical growing season of about 114 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 22
- Average first fall frost
- Sep 16
- Growing season
- 114 days
Safer after Jun 3 (1-in-10 risk)
Possible by Sep 1 (1-in-10 risk)
Last frost typically in 207 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 28 · Jun 7 · Jun 22 | Aug 18 · Sep 1 · Sep 15 | 85 days | 100% |
| Frost / freeze (32°F) | May 9 · May 22 · Jun 3 | Sep 1 · Sep 16 · Sep 28 | 114 days | 100% |
| Hard freeze (28°F) | Apr 24 · May 6 · May 18 | Sep 14 · Sep 28 · Oct 9 | 143 days | 100% |
Planting calendar for Palmer
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 – May 27 |
| 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 6 |
| Summer squash | Sow outdoors | Jun 7 – Jul 22 |
| Winter squash & pumpkins | Sow outdoors | Jun 21 – Jul 22 |
| Snap beans | Sow outdoors | Jun 7 – Jun 29 |
| Sweet corn | Sow outdoors | Jun 7 – May 27 |
| 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 17 – May 27 |
| Broccoli | Transplant outdoors (fall) | Jun 16 – Jun 27 |
| Cabbage | Start seeds indoors (spring) | Mar 24 – Apr 21 |
| Cabbage | Transplant outdoors (spring) | Apr 21 – May 22 |
| Cabbage | Start seeds indoors (fall) | May 7 – Jun 6 |
| Cabbage | Transplant outdoors (fall) | Jun 6 – Jul 7 |
| Leaf lettuce | Sow outdoors (spring) | Apr 21 – Jul 7 |
| Leaf lettuce | Sow outdoors (fall) | Jun 6 – Jul 23 |
| Spinach | Sow outdoors (spring) | Apr 14 – May 28 |
| Spinach | Sow outdoors (fall) | Jun 23 – Jul 28 |
| Radishes | Sow outdoors (spring) | Apr 21 – Jun 11 |
| Radishes | Sow outdoors (fall) | Jun 6 – Aug 7 |
| Kale | Sow outdoors (spring) | May 8 – May 28 |
| Kale | Sow outdoors (fall) | May 30 – Jul 7 |
| Carrots | Sow outdoors (spring) | May 22 – Jul 7 |
| Carrots | Sow outdoors (fall) | May 7 – Jun 22 |
| Garlic | Plant outdoors (fall) | Sep 6 – Oct 7 |
Where these dates come from
ZIP code 99645 is matched to the NOAA station Lazy Mtn, AK, 2.6 km away, at 733 ft elevation (855 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Lazy Mtn, AK (used) | 733 ft | May 22 | Sep 16 |
| Palmer Muni Ap, AK | 230 ft | May 6 | Sep 25 |
| Palmer Job Corps, AK | 216 ft | Apr 24 | Oct 4 |
| Sutton 1 W, AK | 550 ft | Jun 1 | Sep 6 |
Frost dates near Palmer
- Sutton, AK 99674 · last Jun 1, first Sep 6
- Wasilla, AK 99654 · last May 16, first Sep 23
- Chugiak, AK 99567 · last May 21, first Sep 15
- Houston, AK 99694 · last May 29, first Sep 7
- Eagle River, AK 99577 · last May 9, first Sep 26
- Big Lake, AK 99652 · last May 29, first Sep 7
- Willow, AK 99688 · last May 29, first Sep 7
- Anchorage, AK 99504 · last May 1, first Sep 29
Frequently asked questions
- When is the last frost in Palmer, AK?
- For ZIP code 99645, the average last spring frost (32°F) is May 22, based on NOAA 1991-2020 climate normals for the Lazy Mtn, AK weather station. There is a 1-in-10 chance of a frost after June 3.
- When is the first frost in Palmer, AK?
- The average first fall frost (32°F) is September 16. There is a 1-in-10 chance of frost by September 1, so tender plants are at risk from that point on.
- How long is the growing season in 99645?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 114 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.