Honolulu, HI 96721 Frost Dates
Frost dates for Honolulu, HI, ZIP 96721
The last spring frost here typically falls around 04/12, about 227 days from today. The first fall frost typically arrives around 12/01, about 235 frost-free days later.
Zone 12b (55 to 60°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 Honolulu, not a forecast for this year.
What to do before the first frost
Zone 12b around Honolulu has about 14 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
The actual range around Honolulu's last frost
04/12 is the middle of 30 years of NOAA records, not a promise. Plant by 03/13 and you're betting against frost in roughly 9 years out of 10. 05/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Honolulu compares
Honolulu's growing season runs about 235 days, ranking 9,531 of 40,283 US ZIP codes measured here, longest to shortest. Within HI, it ranks 131 of 133.
Learn more
zone vs. frost date explains why Zone 12b and Honolulu's frost date answer different questions, and the frost range explains how to read the range around Honolulu's dates instead of trusting one.