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When to Plant Petunia in Sierra Vista, Arizona (85635)

Location

Sierra Vista, Arizona

ZIP Code

85635

USDA Zone

8b

Last Frost

Sunday, March 15, 2026

📅 Planting Calendar

Start Seeds Indoors Sunday, January 4, 2026
Transplant Outdoors Sunday, March 29, 2026

Pro Tip: Start Petunia seeds indoors 10 weeks before your last frost date, then transplant outdoors around Sunday, March 29, 2026.

🌿 Plant Details

Scientific Name Petunia × hybrida
Days to Maturity 75 days
Mature Height 6-18"
Spread 18"
Type Annual

☀️ Growing Requirements

☀️

Sun

Full Sun (6-8 hours)

💧

Water

Moderate (1 inch/week)

↔️

Spacing

12" apart

🌱

Planting Depth

0.13" deep

Seeds typically germinate in 7-14 days

Ready to Plant Petunia in Sierra Vista?

Get your seeds now so they're ready by Sunday, January 4, 2026.

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🤝 Good Companions

TomatoBasilMarigold

⚠️ Avoid Planting Near

Fennel

Other Plants for Sierra Vista

Growing Petunia in Zone 8b

Petunia (Petunia × hybrida) is a popular garden vegetable. In Sierra Vista, Arizona, which is in USDA Hardiness Zone 8b, you should start seeds indoors around Sunday, January 4, 2026.

Your average last frost date is Sunday, March 15, 2026. Plan to transplant your Petunia seedlings outdoors around Sunday, March 29, 2026, about 2 weeks after your last frost date.