98-105 Days to maturity. Petunia x hybrida. Pelleted Double Madness Series Petunia Seeds. Non-GMO, hybrid, Premium Quality Seeds, annual. Double Madness Series seeds grow a hardy and spectacular alternative to the internationally famous single-blooming petunia. Double Madness petunias promise feathery and double-blooming 3-inch wide papier-mache heads in a variety of signature choices. Double Madness Series petunias mature into neat 10-15 inch tall mounded uprights. Perfect as a tidy grow in beds, borders, edging, or ground cover. Double Madness petunias are easy to grow from seed and are an ideal way to reinvigorate any stale flower bed, patio, or room. Pelleted seeds.