Cabbage in Zone 9a & 9b
Brassica oleracea
When to plant cabbage in zone 9b
Zones 9a and 9b share the same average frost dates in our data, so this page covers both.
Method: Start indoors: Start indoors from seed, then transplant outside. Cabbage needs a head start most zones can't give it by direct-sowing alone.
| Start indoors | Jan 4–Jan 11 |
|---|---|
| Direct sow / transplant outside | Feb 1–Feb 8 |
| Estimated harvest | Apr 12–Apr 19 (~70 days after transplanting) |
Spacing: 1 per square foot (square-foot-gardening spacing). Mature height: 1-1.5 ft.

Cabbage takes up a full square foot for months and won't forgive a rushed transplant date. Start it too late into warm weather and it's more likely to bolt or stall than to head up properly.
How cabbage fits zone 9's season
Zone 9b's frost-free window runs about 293 days, from February 15 to December 5. Cabbage needs about 70 days from transplant to first harvest.
Good companions
- Onion: Onion scent is reputed to confuse cabbage moths. The research behind this is real but garlic-specific (field trials intercropping garlic with cabbage reduced diamondback moth damage) — onion hasn't been tested the same way, so treat the onion version as a reasonable extrapolation, not a directly measured result.
Where to buy cabbage seeds
See why we recommend these suppliers →
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See it growing
Search YouTube for "growing cabbage" videos → (a live search, not a hand-picked video; results vary and aren't vetted by us)
← Back to the full zone 9b calendar · Full companion planting guide · Full plant profile · Plan your beds in the Garden Designer →

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Growing Cabbage in USDA zone 9b: when to start seeds indoors, when to direct-sow, and when to expect a harvest.
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