98-105 days. Growing Double Cascade Series seeds promise to excite your garden with larger, fuller, and brighter petunias than any other this season. Eye-catching Double Cascade petunias steal the show with spectacular 4 inch feathering fully-double blooms ideal for any fresh cut basket, bouquet, or just attracting butterflies to the garden. Double Cascade Series seeds grow early blooming petunias that will delight your home, patio, or garden late into summer. Double Cascade petunias are easy to grow from seed and mature into 10-15 inches tall mounding uprights perfect for borders, fences, walkways, or as an elegant ground cover. Pelleted seeds.