Dahlia Growing Guide
Asteraceae family
Days to Harvest90 days
SunlightFull Sun
Frost ToleranceNone
Spacing18/sqft
Germination7-14 days
HardinessTender
Germ. Temp75°F
Start Indoors6 weeks before last frost
Growth Stages
- Seedling
- Establishing
- Budding
- Blooming
Planting Dates by Zone
| Zone | Start Indoors | Transplant | Direct Sow | Harvest |
|---|---|---|---|---|
| Zone 1a | Apr 13 | Jun 8 | — | Aug 17 |
| Zone 1b | Apr 13 | Jun 8 | — | Aug 17 |
| Zone 2a | Apr 3 | May 29 | — | Aug 7 |
| Zone 2b | Apr 13 | Jun 8 | — | Aug 17 |
| Zone 3a | Apr 10 | Jun 5 | — | Aug 14 |
| Zone 3b | Apr 3 | May 29 | — | Aug 7 |
| Zone 4a | Mar 24 | May 19 | — | Jul 28 |
| Zone 4b | Mar 20 | May 15 | — | Jul 24 |
| Zone 5a | Mar 17 | May 12 | — | Jul 21 |
| Zone 5b | Mar 17 | May 12 | — | Jul 21 |
| Zone 6a | Mar 17 | May 12 | — | Jul 21 |
| Zone 6b | Mar 4 | Apr 29 | — | Jul 8 |
| Zone 7a | Mar 4 | Apr 29 | — | Jul 8 |
| Zone 7b | Feb 27 | Apr 24 | — | Jul 3 |
| Zone 8a | Feb 22 | Apr 19 | — | Jun 28 |
| Zone 8b | Feb 8 | Apr 5 | — | Jun 14 |
| Zone 9a | Feb 6 | Apr 3 | — | Jun 12 |
| Zone 9b | Jan 27 | Mar 24 | — | Jun 2 |
| Zone 10a | Jan 9 | Mar 6 | — | May 15 |
| Zone 10b | Dec 17 | Feb 11 | — | Apr 22 |
| Zone 11a | Dec 17 | Feb 11 | — | Apr 22 |
| Zone 11b | Dec 4 | Jan 29 | — | Apr 9 |
| Zone 12a | Nov 20 | Jan 15 | — | Mar 26 |
| Zone 12b | Nov 20 | Jan 15 | — | Mar 26 |
| Zone 13a | Nov 20 | Jan 15 | — | Mar 26 |
| Zone 13b | Nov 20 | Jan 15 | — | Mar 26 |
Frequently Asked Questions
How long does it take to grow Dahlia?
Dahlia takes approximately 90 days from planting to harvest.
How much sun does Dahlia need?
Dahlia requires full sun (6+ hours direct sunlight per day).
How far apart should I plant Dahlia?
Plant Dahlia at 18/sqft using square foot gardening spacing.
Can Dahlia survive frost?
Dahlia is frost-sensitive and should not be exposed to frost.
How long does Dahlia take to germinate?
Dahlia seeds germinate in 7-14 days at an optimal temperature of 75°F.
When should I start Dahlia seeds indoors?
Start Dahlia seeds indoors 6 weeks before your last frost date, then transplant 2 weeks after last frost.
Plan Your Dahlia Garden
Track Dahlia from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.
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