Hawaii · zones 12a–12a
When to plant sweet potatoes in Hawaii.
Sow or transplant between Feb 7 to Mar 24 in a typical year, keyed to Hawaii's median last frost around Jan 1. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Sweet Potatoes dates for a typical Hawaii season.
1 · Start indoors
Dec 27 to Feb 10
About 6 weeks before set-out. Warm spot, real light.
2 · Set out
Feb 7 to Mar 24
Keyed to the ~Jan 1 last frost. Sow 3" deep, 14" apart.
Harvest
~110 days later
~2.5 lb per plant over ~1 weeks.
Hawaii spans more than one climate: Zone 12 is the most common zone, but the state runs 12a to 12a. 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.