Growing onions in zone 12
Bulbing is triggered by day length: long-day varieties for the North, short-day for the South, intermediate in between — the wrong type simply won’t bulb. Sets are easiest; transplants give bigger bulbs.
Zone 12 covers hawaiʻi lowlands, Puerto Rico — tropical — timing follows wet and dry seasons rather than frost.
Make it local
These windows use zone 12's typical frost dates. For windows computed from your frost dates, run the ZIP code frost lookup and open the planting calendar — it remembers your city. The seed starting scheduler turns the whole seed rack into one printable, date-sorted list.
Frequently asked questions
When should I plant onions in zone 12?
Zone 12 is frost-free, so timing flips from frost-avoidance to heat management: plant onions through the coolest months, typically October to March. Summer heat, not winter cold, is what ends this crop here.
Does onions grow well in zone 12?
Yes, in the right months. Onions is a cool-season crop, so grow it through zone 12's mildest stretch and expect it to bolt or fade as serious heat builds.