Do blue roses exist naturally?
A blue rose is not a naturally occurring flower. A few different tricks are used to create the appearance of color, ranging from imported flowers and dyes to synthetic oils or paint-work on a white petal-less rose. The most reliable method has been proven both effective and safe, but it requires genetic manipulation of in vitro roses by microinjection techniques using DNA fluorotypes (genes that determine flower color) taken from pansies, carnations and other sources of blue pigment. When viewed under a black light typical household lights remain unflavored while fluorescence causes all violet pigments in the test tube flowers to glow intensely with a deep purple coloration—except for those treated with chlorophyll fluorescing an electric yellow light.
Yet such a rose is not blue, but rather purple (with some green lights). As the process of creating such roses would be too time consuming and expensive for the common consumer, blue roses remain a rarity in most florists.