One of the residents, He Tao, said two workers were spraying the grass, turning the yellow grass into green.
Photos uploaded by Netizens showed the council workers spraying a green substance onto the grass.
However, Chengdu city Landscaping Department said the spray wasn't "green paint" but a "greening agent".
Staff from the Landscaping Department of the Urban and Rural Construction Bureau of Longquanyi District claimed it was a coloured nutrient fluid that contains trace amounts of fertiliser that can improve the grass's frost-resistance and appearance.
According to the council, the nutrition deficiency makes the grass turn yellow in winter and if not treated the grass will die by summer.