Petunia

Seed Treatment
Soak seeds in room temperature water for 12–24 hours before sowing to help improve germination.

(Do not soak pelleted seeds)

When to Sow Indoors
Start indoors 8–10 weeks (56–70 days) before your last expected frost.

Optimum Germination Temperature
21–24°C (70–75°F)

Germination Time
7–21 days

Light Requirements for Germination
Seeds need light to germinate. Do not cover with soil.
Use grow lights to maintain 12–16 hours of light per day.

How to Sow Indoors
– Sow on the surface of moist, sterile seed-starting mix
– Press gently to ensure good seed-to-soil contact
– Do not cover with soil
– Keep soil consistently moist but not waterlogged
– Pelleted seeds: Mist gently to help dissolve the coating

Humidity: Use a humidity dome or clear cover to maintain consistent moisture during germination. Open the dome briefly once per day to allow fresh air in and reduce mold risk. Remove the dome entirely once seedlings emerge.

Post-Germination Care & Growing Tips
– Once seedlings have 2–3 true leaves, transplant into individual pots
– Harden off before transplanting outdoors after frost danger has passed
– Final Spacing: 20–30 cm (8–12 in) apart
– Plant Type: Tender perennial often grown as an annual
– Mature Height: 20–40 cm (8–16 in) depending on variety
– Grows best in full sun and rich, well-drained soil
– Pinch back young plants to encourage bushier growth and more blooms
– Regular deadheading will promote continuous flowering