my LocalPlanting

When to Plant Petunia in Zone 12A

USDA Zone

12A

Cities Covered

25

Avg Last Frost

Thursday, January 1, 2026

Plant Type

Indoor Start

📅 Planting Calendar for Zone 12A

Start Seeds Indoors Thursday, October 23, 2025
Transplant Outdoors Thursday, January 15, 2026

Pro Tip: Start Petunia seeds indoors 10 weeks before your last frost date for best results.

🌿 Plant Details

Scientific Name Petunia × hybrida
Days to Maturity 75 days
Sun Requirements Full Sun (6-8 hours)
Plant Spacing 12" apart

Cities in Zone 12A

Other Plants for Zone 12A

Browse Other Zones

Growing Petunia in USDA Zone 12A

Petunia (Petunia × hybrida) grows well in USDA Hardiness Zone 12A. This zone includes cities like Aiea, Anahola, Haiku and 22 more.

The average last frost date for Zone 12A is around Thursday, January 1, 2026. For best results, start your Petunia seeds indoors around Thursday, October 23, 2025, then transplant outdoors around Thursday, January 15, 2026.

Expect to harvest your Petunia approximately 75 days after planting.