Growing Welsh Onion in Zone 10a
Zone 10a has a year-round growing season. Welsh Onion 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)
When to Plant Welsh Onion in Zone 10a
Start Seeds Indoors: Dec 12
Start Welsh Onion seeds indoors around Dec 12 (10 weeks before last frost). Optimal germination temperature: 70°F. Germinates in 7–14 days.
Transplant Outdoors: Jan 23
Transplant Welsh Onion seedlings outdoors after Jan 23. Wait until soil temperature reaches 45°F. Space plants at 6/sqft. Harden off plants for a week before moving outside.
Harvest: Apr 13
First harvest approximately Apr 13 (~80 days from transplant). Continue harvesting until first frost (Dec 1).
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 10a?
Start Welsh Onion seeds indoors around Dec 12. Transplant outdoors after Jan 23. Expect first harvest around Apr 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 Welsh Onion in Zone 10a?
Yes. Welsh Onion needs 60 days to harvest. Zone 10a has a 284-day growing season, which is sufficient.
What is the best month to plant Welsh Onion in Zone 10a?
The best time to start Welsh Onion in Zone 10a is Dec. Begin seeds indoors around Dec 12, then transplant outdoors after the last frost date of Feb 20.
How long does Welsh Onion take to harvest?
Welsh Onion takes approximately 60 days from planting to harvest. In Zone 10a, expect your first harvest around Apr 13.
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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