Zone 10B — September
What to Plant in September in Zone 10B
September in Zone 10B:
1 crop to start indoors,
0 to plant or direct sow outside, and
4 entering harvest window.
About 1 winter in 9 freezes; in those winters the last frost averages January 11. Reference city: Los Angeles, CA.
1 Start Indoors
0 Plant Outside
4 Harvest
Start Indoors in September
| Plant | Type | Start Indoors | Transplant Outside | Harvest Window |
|---|---|---|---|---|
| Texas 1015Y SuperSweet Onion | allium | Sep 14 | Dec 14 | Mar 29 – Apr 8 |
Plant Outside in September
Nothing to plant or sow outside in September for Zone 10B.
Next window: October — 7 varieties, including Asian Tempest Garlic, Chengdu Garlic, Creole Red Garlic.
Harvest in September
| Plant | Type | Planted / Sown | Harvest Window |
|---|---|---|---|
| Culinary Turmeric | root vegetable | Feb 1 | Sep 29 – Nov 28 |
| Ginger | root vegetable | Feb 1 | Sep 29 – Nov 28 |
| Broadleaf Full Heart Batavian Endive | lettuce | Jun 16 | Sep 9 – Sep 14 |
| Verona Red Chicory | lettuce | Jun 16 | Sep 9 – Sep 16 |
Key Tasks for September in Zone 10B
- 1 Start 1 variety indoors this month under grow lights or in a sunny south-facing window. Use a seed-starting mix and bottom heat (70–75°F) for best germination rates.
- 2 Apply 2–3 inches of mulch around heat-sensitive crops to retain moisture and keep root zones cooler. Water deeply and less frequently rather than shallow daily watering.
- 3 Begin fall cool-season planting window this month. Direct sow lettuce, spinach, arugula, and radishes now for harvest before hard frost.
- 4 Check soil moisture before watering — stick a finger 2 inches into the soil. Water only when the soil is dry at that depth. Consistent moisture is more important than frequency.
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