Palmer Municipal Airport, AK Frost Dates & Growing Season

The two dates every Palmer Municipal Airport garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
May 6
~50% chance of frost after
First fall frost
Sep 25
~50% chance of frost before
Growing season
142 days
frost-free stretch
USDA zone
≈ 4b
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Apr 24 May 6 May 18
First fall frost Oct 8 Sep 25 Sep 11
Hard freeze (28°F), median last Apr 24 · first Oct 3

Computed from NOAA 1991–2020 climate normals at the PALMER MUNI AP station. "Safe" means frost past that date happens only about one year in ten. Your exact garden can still run days either way with elevation and terrain — check your own ZIP with the frost date lookup.

Planting windows for Palmer Municipal Airport

Computed from Palmer Municipal Airport's own frost dates. Click any crop for the full zone-4 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Mar 11 – Mar 25 May 13 – May 20
🫑 Peppers Feb 25 – Mar 11 May 20 – May 27
🥬 Lettuce Mar 25 – Apr 8 Apr 8 – Apr 22 Apr 8 – May 6
🫛 Peas Mar 25 – Apr 8
🥕 Carrots Apr 15 – May 6
🥦 Broccoli Mar 18 – Apr 1 Apr 15 – Apr 29
🥬 Kale Mar 25 – Apr 8 Apr 8 – Apr 22 Apr 8 – Apr 22
🥒 Cucumbers Apr 8 – Apr 15 May 13 – May 20 May 13 – May 20
🥒 Zucchini Apr 8 – Apr 15 May 13 – May 20 May 13 – May 20
🫘 Green Beans (Bush) May 13 – May 20
🌽 Sweet Corn May 13 – May 20
🌿 Basil Mar 25 – Apr 8 May 13 – May 20 May 20 – May 27
🧄 Garlic Fall: Aug 14 – Sep 11

Want this for all 50 crops, or as a printable seed-shelf schedule? Use the planting calendar and the seed starting scheduler — both can use Palmer Municipal Airport's dates automatically after a lookup.

Reading the season in Palmer Municipal Airport

At about 142 frost-free days, Palmer Municipal Airport rewards efficiency: start warm-season crops indoors, favor short-season varieties, and lean on cold-tolerant crops — peas, kale, roots — that shrug off the shoulder-season frosts on either end.

Frequently asked questions

When is the last frost in Palmer Municipal Airport, AK?

The average last spring frost in Palmer Municipal Airport is around May 6, based on 1991–2020 climate normals. That's a median — about half of years see a later frost, so tender crops are safest going out a week or two after this date.

When is the first frost in Palmer Municipal Airport, AK?

The average first fall frost in Palmer Municipal Airport arrives around Sep 25. Crops still in the garden need to mature before then, and frost-tender plants need harvesting or protection as the date approaches.

How long is the growing season in Palmer Municipal Airport?

About 142 frost-free days on average, from May 6 to Sep 25. That favors short-season varieties and transplants for warm-season crops, with cool-season vegetables doing the heavy lifting in spring and fall.

What USDA zone is Palmer Municipal Airport in?

USDA zone 4b on the 2023 Plant Hardiness Zone Map. Note that zones describe winter cold, not frost timing — these frost dates are the numbers to plan plantings around.