Petunia x hybrida Grandiflora Beautiful trumpet shaped, 10-12 cm (4-5″) purple flowers with pronounced darker veins bloom early summer to fall on these very robust, compact 25-38 cm (12-15″) plants. Excellent disease resistance, weather tolerance and overall garden performance! How to Grow Start seed indoors in a soil-less mix 6-8 weeks before planting out time. Since the seed is so small, leave it uncovered on the surface of the growing medium. Pelleted seed must be lightly misted after sowing until the seed coating dissolves completely or germination may not occur at all. Apply bottom heat to keep the growing medium temperature at 25 C (77 F) for the 14 day germination period. After germination, grow on under lights at a cooler temperature of 15 C (60 F) until hardening off and planting out to a sunny spot in late May. Space plants 20 cm (8″) apart in the garden. Annual. Approx 30 seeds/pkt.