Greenery Day in Japan
Greenery Day in Japan is held on May 4. みどりの日 - Until 1988, April 29 was celebrated as the birthday of Emperor Showa. It was decided to keep this day a holiday even after his passing away in January 1989 and to name it Greenery Day because of the late Emperor's love of nature. In 2007, April 29 became Showa Day, and Greenery Day was moved to May 4. This event in the first decade of the month may is annual.
Green Up Day in Vermont on May 1 (observed on the first Saturday of May, is a statewide effort in the US state of Vermont to clean up roadside trash);
Spring Decade of Birdwatching on May 1 (May 1-10);
Energy Conservation Week in Ontario, Canada on May 16 (is about the power of collective action);