The highlights of Rohlf’s work include his watercolours and the late water tempera sheets. Along with the watercolours by Emil Nolde, Karl Schmidt-Rottluff and August Macke, they are among the most important examples of German art of the first half of the 20th century. While the aforementioned artists often place their motifs wet-on-wet directly on the paper, Rohlfs has developed a special technique with which he superimposes the colors in an almost glazed manner.