Petunias are (grown as annuals in most climates). 👉 Never plant outdoors until after the last spring frost. Soil temperature should be at least 60°F (15°C) — ideally 65°F (18°C).
: Petunias require full sun to generate energy; insufficient light leads to slow growth and fewer flowers. when to grow petunias
Petunias are warm-season bloomers that cannot tolerate freezing temperatures. Therefore, the "perfect" time to grow them depends on your climate and whether you are starting from seed or planting seedlings. Petunias are (grown as annuals in most climates)
: Seedlings should only be moved outside once the danger of frost has completely passed . Regional Benchmarks : Zones 7a/7b : Aim for transplanting around mid-April . Zones 8a/8b : Aim for transplanting around mid-March . : Petunias require full sun to generate energy;
| Action | Timing | | :--- | :--- | | | 10–12 weeks before last frost. | | Harden Off Plants | 1 week before last frost. | | Transplant Outside | 1–2 weeks after last frost. | | Soil Temperature | Minimum 60°F (15°C). |