The first time you saw Rainbow Roses—or mums or carnations, similarly tinted—did you do a double-take? You can tell by the texture of the petals that the flowers are real and have not been spray-painted. But how do they get all those vivid colors (usually four but sometimes even more) into one flower?
The answer lies in a surprisingly simple technique that has actually been practiced for hundreds of years, if not on the scale that we see commercially today. It can even be done at home. As with any stem-dyed flower, the cut stem end is immersed in a solution containing the dye (ideally, a special floral dye—food coloring will not produce quite the same effect). The difference with Rainbow Roses is that the stem is first split into sections, usually quarters. It’s in the nature of the rose’s vascular system that colored water absorbed by one section of the stem will flow into the petals at the top still divided by sections, so that petals in each quadrant turn a different hue.
The technique works best with white flowers like the hybrid tea rose cultivar ‘Vendela’, a favorite for creating Rainbow Roses. In Colombia and Ecuador, where most of America’s roses are grown, it is applied to roses and other flowers right on the farm before they are shipped to markets in the U.S.
Love it or hate it, the Rainbow Rose gets attention! Although the look is hardly natural, it gives a dramatic demonstration of how water and nutrients are transported up from the soil into the leaves and petals of a rose. And there we have one of Mother Nature’s miracles.