Alaska · zones 3a8a

When to plant kale in Alaska.

Sow or transplant between Apr 4 to May 2 in a typical year, keyed to Alaska's median last frost around May 12. A second, fall sowing fits Jun 15 to Jul 31. Dates below are state medians; your ZIP code shifts them by days to weeks.

The 2026 windows

Kale dates for a typical Alaska season.

1 · Start indoors

Feb 21 to Mar 21

About 6 weeks before set-out. Warm spot, real light.

2 · Set out

Apr 4 to May 2

Keyed to the ~May 12 last frost. Sow 0.25" deep, 16" apart.

Fall round

Jun 15 to Jul 31

Counted back from the ~Sep 15 first frost.

Harvest

~45 days later

~2 lb per plant over ~16 weeks.

Alaska spans more than one climate: Zone 3 is the most common zone, but the state runs 3a to 8a. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.

In Alaska: watch for

The pests that find kale here.

The short season here, about 126 frost-free days, keeps kale in front of cabbage worms & loopers only briefly. One early row cover usually carries a planting through the worst of it.

Cabbage worms & loopers

Green caterpillars chewing ragged holes; green droppings.

Organic fix: Handpick, cover with netting, spray Bt.

Aphids

Gray-green clusters tucked into the leaf folds.

Organic fix: Blast with water, then insecticidal soap.

Flea beetles

Tiny holes peppering the young leaves.

Organic fix: Row cover from day one; diatomaceous earth.

Black rot

Yellow V-shaped wedges cutting in from the leaf edge, veins blackening inside.

Organic fix: Pull infected plants, water at the base, keep brassicas out of that bed 3 years.

Cabbage root maggot

Seedlings wilt, yellow and stall for no reason; white maggots tunnel the roots.

Organic fix: Row cover before the flies are up, when yellow rocket blooms; rotate the bed.

Your season math: Alaska gives kale about 126 frost-free days, and it needs roughly 45 days to a first harvest. It's a one-planting crop, so time that single sowing well.

Planting kale in Alaska: questions

When should I plant kale in Alaska?+

In a typical Alaska year, sow kale or set out transplants between Apr 4 to May 2, keyed to the state's median last frost around May 12. There's also a fall window: Jun 15 to Jul 31. Your exact dates shift with your ZIP code and microclimate.

When do I start kale seeds indoors in Alaska?+

Start seeds inside about 6 weeks before set-out: roughly Feb 21 to Mar 21 for a typical Alaska season.

What USDA zone is Alaska?+

Alaska spans zones 3a–8a, mostly zone 3. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.

How many kale plants do I need?+

Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.