Rainbow roses are displayed at the 36th international flower expo in St.Paul, Brazil on Thursday. The rainbow rose is a rose that has had its petals artificially colored. The method exploits the rose’s natural processes by which water is drawn up the stem. By splitting the stem and dipping each part in different colored water, the colors are drawn into the petals, resulting in a multicolored rose. These color changes to the rose make it live shorter than an uncolored one.