Growing Watercress in Zone 10a
Zone 10a has a year-round growing season. Watercress can be planted almost any time with proper planning. Last frost: Feb 20. First frost: Dec 1.
Planting Calendar
Season: Feb 20 – Dec 1 (284 days) · Succession: plant every 2 weeks (up to 16x)
When to Plant Watercress in Zone 10a
Start Seeds Indoors: Jan 9
Start Watercress seeds indoors around Jan 9 (6 weeks before last frost). Optimal germination temperature: 60°F. Germinates in 7–14 days.
Transplant Outdoors: Feb 6
Transplant Watercress seedlings outdoors after Feb 6. Wait until soil temperature reaches 45°F. Space plants at 6/sqft. Harden off plants for a week before moving outside.
Harvest: Mar 13
First harvest approximately Mar 13 (~35 days from transplant). Continue harvesting until first frost (Dec 1). Watercress can overwinter in mild climates for continued harvest.
Fall Planting: Oct 20
For a fall harvest, plant Watercress around Oct 20 (6 weeks before first frost).
Watercress in Other Zones
1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13bFrequently Asked Questions
When should I plant Watercress in Zone 10a?
Start Watercress seeds indoors around Jan 9. Transplant outdoors after Feb 6. Expect first harvest around Mar 13.
What is the last frost date for Zone 10a?
The average last spring frost date for Zone 10a is Feb 20. The first fall frost averages Dec 1, giving a 284-day growing season.
Can I grow Watercress in Zone 10a?
Yes. Watercress needs 50 days to harvest. Zone 10a has a 284-day growing season, which is sufficient. You can plant up to 16 successions.
What is the best month to plant Watercress in Zone 10a?
The best time to start Watercress in Zone 10a is Jan. Begin seeds indoors around Jan 9, then transplant outdoors after the last frost date of Feb 20.
How long does Watercress take to harvest?
Watercress takes approximately 50 days from planting to harvest. In Zone 10a, expect your first harvest around Mar 13.
Plan Your Watercress Garden
Track Watercress from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.
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