Field guide
When to plant zucchini in USDA Zones 9–10
In USDA Zones 9–10, the planner’s broad outdoor planting window for zucchini runs from March to April, with a second window from August. Zucchini takes 45–65 days from planting to first harvest.
Open plannerPlanting calendar for USDA Zones 9–10
- Spring planting
- March to April
- Fall planting
- August
- Days to harvest
- 45–65 days
- Water needs
- high
What USDA Zones 9–10 do—and do not—tell you
These zones span average annual extreme minimum temperatures of roughly 20°F to 40°F. That is useful climate context, but it does not determine your exact frost dates. Check a local forecast or county Extension calendar before planting tender crops.
How to know when to harvest
- Best at 6-8 inches — don't let them turn into baseball bats
- Skin should be shiny and tender enough to dent with a fingernail
- Check daily once fruiting starts — they can double in size overnight
Want a plan that accounts for your crops, growing method, equipment, and plant conditions? Open the free planner for a daily crop checklist and adaptive harvest forecast.
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