Growing Dahlia in Zone 6b
Zone 6b has mild winters and a long growing season — good conditions for Dahlia. Last frost: Apr 15. First frost: Oct 22.
Planting Calendar
Season: Apr 15 – Oct 22 (190 days)
When to Plant Dahlia in Zone 6b
Start Seeds Indoors: Mar 4
Start Dahlia seeds indoors around Mar 4 (6 weeks before last frost). Optimal germination temperature: 75°F. Germinates in 7–14 days.
Transplant Outdoors: Apr 29
Transplant Dahlia seedlings outdoors after Apr 29. Wait until soil temperature reaches 60°F. Space plants at 18/sqft. Harden off plants for a week before moving outside.
Harvest: Jul 8
First harvest approximately Jul 8 (~70 days from transplant). Continue harvesting until first frost (Oct 22).
Dahlia 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 Dahlia in Zone 6b?
Start Dahlia seeds indoors around Mar 4. Transplant outdoors after Apr 29. Expect first harvest around Jul 8.
What is the last frost date for Zone 6b?
The average last spring frost date for Zone 6b is Apr 15. The first fall frost averages Oct 22, giving a 190-day growing season.
Can I grow Dahlia in Zone 6b?
Yes. Dahlia needs 90 days to harvest. Zone 6b has a 190-day growing season, which is sufficient.
What is the best month to plant Dahlia in Zone 6b?
The best time to start Dahlia in Zone 6b is Mar. Begin seeds indoors around Mar 4, then transplant outdoors after the last frost date of Apr 15.
How long does Dahlia take to harvest?
Dahlia takes approximately 90 days from planting to harvest. In Zone 6b, expect your first harvest around Jul 8.
Plan Your Dahlia Garden
Track Dahlia from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.
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