my LocalPlanting

When to Plant Dahlia in Zone 11B

USDA Zone

11B

Cities Covered

14

Avg Last Frost

Thursday, January 1, 2026

Plant Type

Indoor Start

📅 Planting Calendar for Zone 11B

Start Seeds Indoors Thursday, November 20, 2025
Transplant Outdoors Thursday, January 8, 2026

Pro Tip: Start Dahlia seeds indoors 6 weeks before your last frost date for best results.

🌿 Plant Details

Scientific Name Dahlia pinnata
Days to Maturity 90 days
Sun Requirements Full Sun (6-8 hours)
Plant Spacing 18" apart

Cities in Zone 11B

Other Plants for Zone 11B

Browse Other Zones

Growing Dahlia in USDA Zone 11B

Dahlia (Dahlia pinnata) grows well in USDA Hardiness Zone 11B. This zone includes cities like Long Key, Islamorada, Key West and 11 more.

The average last frost date for Zone 11B is around Thursday, January 1, 2026. For best results, start your Dahlia seeds indoors around Thursday, November 20, 2025, then transplant outdoors around Thursday, January 8, 2026.

Expect to harvest your Dahlia approximately 90 days after planting.