A Heartwarming Little Treasure. Kusamono is a delicate branch of Japanese bonsai art, featuring compositions of soft-stemmed plants such as grasses, mosses, ferns, and wildflowers. The word itself combines “Kusa” (grass, plant) and “Mono” (thing). Kusamono often appears as a standalone decorative piece, but it is also commonly placed beside a bonsai tree to complement it—especially in exhibitions or seasonal installations.