Onion in Zone 10a
Allium cepa
Method: Start indoors — Start indoors from seed, then transplant outside — Onion needs a head start most zones can't give it by direct-sowing alone.
| Start indoors | Aug–Nov |
|---|---|
| Direct sow / transplant outside | Oct–Jan |
| Estimated harvest | ~100 days after transplanting |
Spacing: 9 per square foot (square-foot-gardening spacing).
Zone 10a dates sourced from growinginthegarden.com.
Good companions
- Carrot — Mutual pest confusion between the two root crops.
- Tomato — Onion scent can deter tomato pests.
Where to buy onion seeds
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See it growing
Search YouTube for "growing onion" videos → (a live search, not a hand-picked video — results vary and aren't vetted by us)
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