A boy helps water flowers at a rooftop garden in the Erlizhuang community of Beijing's Haidian district, on April 16, 2020. The rooftop garden is designed by local residents and a workshop, and it is an important link in the community's garbage classification. The nutrient soil is made from kitchen waste. (Photos by Zou Hong/chinadaily.com.cn)

A boy paints on the ground to decorate the rooftop garden in the Erlizhuang community of Beijing's Haidian district, on April 16, 2020.

A section of the rooftop garden in the Erlizhuang community of Beijing's Haidian district is designed to use kitchen waste for planting.