Kachemak, AK 99603 Frost Dates
When can you plant in Kachemak, AK?
Typically, the last spring freeze lands around 05/10, roughly 255 days out. The first fall frost typically arrives around 09/29, about 141 frost-free days later.
The USDA Plant Hardiness Zone Map puts Kachemak in Zone 6a (-10 to -5°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
About 5 weeks of growing season left in Kachemak before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
05/10 is the middle of 30 years of NOAA records, not a promise. Plant by 04/27 and you're betting against frost in roughly 9 years out of 10. 05/23 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Kachemak compares
About 141 days separate Kachemak's last and first frost, putting it 36,957 of 40,283 ZIP codes nationally. Within AK, it ranks 66 of 269.
Learn more
local microclimates covers what one yard in Kachemak can differ from the 99603 normal. zone vs. frost date covers why Zone 6a and Kachemak's frost date answer different questions.