Growing Rhubarb in Zone 12b
Zone 12b has a year-round growing season. Rhubarb can be planted almost any time with proper planning. Last frost: Jan 1. First frost: Dec 31.
Planting Calendar
Season: Jan 1 – Dec 31 (364 days)
When to Plant Rhubarb in Zone 12b
Start Seeds Indoors: Oct 23
Start Rhubarb seeds indoors around Oct 23 (10 weeks before last frost). Optimal germination temperature: 65°F. Germinates in 7–21 days.
Transplant Outdoors: Dec 4
Transplant Rhubarb seedlings outdoors after Dec 4. Wait until soil temperature reaches 40°F. Space plants at 1/sqft (12" apart). Harden off plants for a week before moving outside.
Harvest: Dec 4
First harvest approximately Dec 4 (~365 days from transplant). Continue harvesting until first frost (Dec 31). Rhubarb can overwinter in mild climates for continued harvest.
Rhubarb 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 Rhubarb in Zone 12b?
Start Rhubarb seeds indoors around Oct 23. Transplant outdoors after Dec 4. Expect first harvest around Dec 4.
What is the last frost date for Zone 12b?
The average last spring frost date for Zone 12b is Jan 1. The first fall frost averages Dec 31, giving a 364-day growing season.
Can I grow Rhubarb in Zone 12b?
Yes. Rhubarb needs 90 days to harvest. Zone 12b has a 364-day growing season, which is sufficient.
What is the best month to plant Rhubarb in Zone 12b?
The best time to start Rhubarb in Zone 12b is Oct. Begin seeds indoors around Oct 23, then transplant outdoors after the last frost date of Jan 1.
How long does Rhubarb take to harvest?
Rhubarb takes approximately 90 days from planting to harvest. In Zone 12b, expect your first harvest around Dec 4.
Plan Your Rhubarb Garden
Track Rhubarb from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.
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