Petunia atkinsiana Tidal Wave Silver HybridPetunia Seeds (Hedgeiflora) Terrific flower power with a more aggressive plant habit. Dense, mounded plants billow with vibrant flowers. Plant height is determined by spacing……the closer together they are, the taller they\’ll grow. Average height is 40-55cm (16-22\”), farther apart they\’ll be more ground-cover like in habit spreading up to 1m (3\’) wide. 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 25C (77F) for the 14 day germination period. After germination, grow on under lights at a cooler temperature of 15C (60F) until hardening off and planting out to a sunny spot in late May. Space plants 25cm (10\”) apart in the garden. Annual. Approx.8 Seeds/pkt.