Growing Welsh Onion in Zone 10b
Zone 10b has a year-round growing season. Welsh Onion 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)
When to Plant Welsh Onion in Zone 10b
Start Seeds Indoors: Nov 19
Start Welsh Onion seeds indoors around Nov 19 (10 weeks before last frost). Optimal germination temperature: 70°F. Germinates in 7–14 days.
Transplant Outdoors: Dec 31
Transplant Welsh Onion seedlings outdoors after Dec 31. Wait until soil temperature reaches 45°F. Space plants at 6/sqft. Harden off plants for a week before moving outside.
Harvest: Mar 21
First harvest approximately Mar 21 (~80 days from transplant). Continue harvesting until first frost (Dec 22).
Welsh Onion 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 Welsh Onion in Zone 10b?
Start Welsh Onion seeds indoors around Nov 19. Transplant outdoors after Dec 31. Expect first harvest around Mar 21.
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 Welsh Onion in Zone 10b?
Yes. Welsh Onion needs 60 days to harvest. Zone 10b has a 328-day growing season, which is sufficient.
What is the best month to plant Welsh Onion in Zone 10b?
The best time to start Welsh Onion in Zone 10b is Nov. Begin seeds indoors around Nov 19, then transplant outdoors after the last frost date of Jan 28.
How long does Welsh Onion take to harvest?
Welsh Onion takes approximately 60 days from planting to harvest. In Zone 10b, expect your first harvest around Mar 21.
Plan Your Welsh Onion Garden
Track Welsh Onion from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.
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