Grimm gained much of his present-day fame by painting landscapes of southern California in the 1920s. Many works depict alluvial fans and desert vegetation in the eastern half of Riverside County. The San Jacinto Mountains appear frequently in his work. Most of the works are oil on canvas. To a viewer untrained in art, his work looks similar to desert landscapes of Karl Albert (1911- ). A residence on Calle Palo Fierro in the Palm Springs Warm Sands Neighborhood was built for him in 1935. He had a studio on Palm Canyon Drive in Palm Springs from the 1950s until his death in 1974.