Platinum, AK 99651 Frost Dates
When can you plant in Platinum, AK?
Around 05/21 is the usual last spring frost, about 266 days away. The first fall frost typically arrives around 09/22, about 122 frost-free days later.
Zone 4b (-25 to -20°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Platinum, not a forecast for this year.
What to do before the first frost
About 4 weeks of growing season left in Platinum before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 05/21 isn't a guarantee
05/21 is the middle of 30 years of NOAA records, not a promise. Plant by 05/08 and you're betting against frost in roughly 9 years out of 10. 06/02 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Platinum compares
Platinum's growing season runs about 122 days, ranking 38,987 of 40,283 US ZIP codes measured here, longest to shortest. Within AK, it ranks 131 of 269.
Learn more
the frost range covers how to read the range around Platinum's dates instead of trusting one. local microclimates covers what one yard in Platinum can differ from the 99651 normal.