Marigold Seeds - Bonanza Series56 63 days. Bonanza Series marigold seeds are brilliant, easy to grow, and renowned for their hardiness and ability to thrive where other novelty plants can not. Bonanza Series marigold is an AAS Bedding Plant Winner for its unique design" and "season long flower color." Bonanza Series seeds mature to a compact 8 12 shrub with lush 2" blooms tidy enough for indoor gardening, yet robust enough to flourish outside in the long summer heat. Bonanza Series