Vegetable · Dioscoreaceae
When to plant yams
A tropical climber, unrelated to the sweet potato despite the shared name in North America, and needing an even longer warm season.
Plant out
2 weeks after
Counted from your last spring frost.
Days to maturity
240-300
From sowing to a first picking.
Hardy in USDA zones
9a to 11a
Winter cold sets the limit here, not the calendar.
Those weeks become real dates once you name a place.
Timing, in frost-relative terms
Seed packets rarely give calendar dates, because a date that suits one latitude is wrong at another. They give offsets from the last spring frost instead, and those offsets are what make yams plantable anywhere.
- Plant out 2 weeks after the last frost.
- Expect 240–300 days to maturity, counted from sowing.
- Hardy in USDA zones 9a–11a.
Frost tolerance
No frost tolerance whatsoever.
Classified as tender, with damage expected below 0°C (32°F)32°F (0°C).