📍 Marietta, NC · Zone 8b · Last frost Sunday, March 15, 2026
✏️ ChangeWhen to Plant Dahlia in Marietta, North Carolina (28362)
Location
Marietta, North Carolina
ZIP Code
28362
USDA Zone
8b
Last Frost
Sunday, March 15, 2026
📅 Your 2026 Planting Dates
Start Seeds Indoors
Sunday, February 1, 2026
Transplant Outdoors
Sunday, March 22, 2026
Based on last frost Sunday, March 15, 2026 · Zone 8b
Pro tip: Start Dahlia seeds indoors 6 weeks before your last frost date, then transplant outdoors around Sunday, March 22, 2026.
🌿 Plant Details
☀️ Growing Requirements
☀️
Sun
Full Sun (6-8 hours)
💧
Water
Regular (1-2 inches/week)
↔️
Spacing
18" apart
🌱
Planting Depth
4" deep
Seeds typically germinate in 7-14 days
Ready to Plant Dahlia in Marietta?
Get your seeds now so they're ready by Sunday, February 1, 2026.
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🤝 Good Companions
Full Companion Planting Guide for Dahlia
See which plants help Dahlia thrive, which to keep away, and raised bed layout tips →
🛠️ Supplies You'll Need
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🌾 Seed Saving Guide
🟡 ModerateWhen to Harvest Seed
Allow seed pods (behind the flower) to dry on the plant in fall.
Processing
Remove dried seed pods, extract flat seeds, dry 1 week in an open envelope.
Seed Viability
Up to 2 years when stored cool, dark, and dry.
Pro Tip
Dahlia seeds do not grow true to the parent — each seedling is a unique hybrid. Propagate named varieties by tuber division.
Raised Bed Planting Guides
A 4×8 bed fits 14 plants of Dahlia. See plant counts, spacing grids, and companion pairings for every bed size →
Frequently Asked Questions
When should I plant Dahlia in Marietta, North Carolina? +
In Marietta (Zone 8b), start Dahlia seeds indoors around Sunday, February 1, 2026 and transplant outdoors around Sunday, March 22, 2026.
What is the last frost date for Marietta, North Carolina? +
The average last spring frost date for Marietta, North Carolina (ZIP 28362) is around Sunday, March 15, 2026. This is based on NOAA climate normals for USDA Zone 8b.
How long does Dahlia take to grow? +
Dahlia typically matures in about 90 days from transplanting. In Marietta, that means you can expect harvest around Sunday, March 22, 2026 plus 90 days.
Should I start Dahlia indoors or direct sow in North Carolina? +
Dahlia should be started indoors 6 weeks before your last frost date. In Marietta, that means starting around Sunday, February 1, 2026.
Other Plants for Marietta
Growing Dahlia in Zone 8b
Dahlia (Dahlia pinnata) is a popular garden vegetable. In Marietta, North Carolina, which is in USDA Hardiness Zone 8b, you should start seeds indoors around Sunday, February 1, 2026.
Your average last frost date is Sunday, March 15, 2026. Plan to transplant your Dahlia seedlings outdoors around Sunday, March 22, 2026, about 1 weeks after your last frost date.