Growing Petunia in Zone 10b
Zone 10b has a year-round growing season. Petunia 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 Petunia in Zone 10b
Start Seeds Indoors: Nov 19
Start Petunia seeds indoors around Nov 19 (10 weeks before last frost). Optimal germination temperature: 75°F. Germinates in 7–14 days.
Transplant Outdoors: Feb 4
Transplant Petunia seedlings outdoors after Feb 4. Wait until soil temperature reaches 60°F. Space plants at 10/sqft. Harden off plants for a week before moving outside.
Harvest: Mar 21
First harvest approximately Mar 21 (~45 days from transplant). Continue harvesting until first frost (Dec 22).
Petunia 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 Petunia in Zone 10b?
Start Petunia seeds indoors around Nov 19. Transplant outdoors after Feb 4. 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 Petunia in Zone 10b?
Yes. Petunia needs 60 days to harvest. Zone 10b has a 328-day growing season, which is sufficient.
What is the best month to plant Petunia in Zone 10b?
The best time to start Petunia 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 Petunia take to harvest?
Petunia takes approximately 60 days from planting to harvest. In Zone 10b, expect your first harvest around Mar 21.
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