Growing Watercress in Zone 10b
Zone 10b has a year-round growing season. Watercress can be planted almost any time with proper planning. Last frost: Jan 28. First frost: Dec 22.
Planting Calendar
Season: Jan 28 – Dec 22 (328 days) · Succession: plant every 2 weeks (up to 19x)
When to Plant Watercress in Zone 10b
Start Seeds Indoors: Dec 17
Start Watercress seeds indoors around Dec 17 (6 weeks before last frost). Optimal germination temperature: 60°F. Germinates in 7–14 days.
Transplant Outdoors: Jan 14
Transplant Watercress seedlings outdoors after Jan 14. Wait until soil temperature reaches 45°F. Space plants at 6/sqft. Harden off plants for a week before moving outside.
Harvest: Feb 18
First harvest approximately Feb 18 (~35 days from transplant). Continue harvesting until first frost (Dec 22). Watercress can overwinter in mild climates for continued harvest.
Fall Planting: Nov 10
For a fall harvest, plant Watercress around Nov 10 (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 10b?
Start Watercress seeds indoors around Dec 17. Transplant outdoors after Jan 14. Expect first harvest around Feb 18.
What is the last frost date for Zone 10b?
The average last spring frost date for Zone 10b is Jan 28. The first fall frost averages Dec 22, giving a 328-day growing season.
Can I grow Watercress in Zone 10b?
Yes. Watercress needs 50 days to harvest. Zone 10b has a 328-day growing season, which is sufficient. You can plant up to 19 successions.
What is the best month to plant Watercress in Zone 10b?
The best time to start Watercress in Zone 10b is Dec. Begin seeds indoors around Dec 17, then transplant outdoors after the last frost date of Jan 28.
How long does Watercress take to harvest?
Watercress takes approximately 50 days from planting to harvest. In Zone 10b, expect your first harvest around Feb 18.
Plan Your Watercress Garden
Track Watercress from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.
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