Ruby, AK 99768 Frost Dates
Ruby, AK: when does the frost end?
Around 05/18 is the usual last spring frost, about 263 days away. Fall's first freeze usually shows up around 09/08, roughly 111 days after the last spring frost.
Zone 3a (-40 to -35°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 Ruby, not a forecast for this year.
Stretching the season past the first frost
With roughly 2 weeks until Ruby's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Ruby's last frost
05/18 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/08 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/01 and only about 1 year in 10 sees frost after that.
Ruby against the rest of the dataset
Ruby's growing season runs about 111 days, ranking 39,485 of 40,283 US ZIP codes measured here, longest to shortest. Within AK, it ranks 161 of 269.
Learn more
Before leaning on 99768's figures: zone vs. frost date explains why Zone 3a and Ruby's frost date answer different questions, while the frost range explains how to read the range around Ruby's dates instead of trusting one.