As the story goes, Yayoi Kusama spent her formative years among the greenhouses and fields of her family’s nursery in the mountainous city of Matsumoto, Japan. The artist’s latest show, “Kusama: Cosmic Nature” at the New York Botanical Garden, explores her deeply rooted relationship with flora, fauna, and the natural world. Displayed across 50 acres of lush grounds, Kusama’s otherworldly, plant-inspired sculptures transport visitors into what might look like the artist’s childhood fantasy realm.