A blue rose is a flower of the genus Rosa (family Rosaceae) that presents blue-to-violet pigmentation instead of the more common red, white, or yellow. Blue roses are often portrayed in literature and art as a symbol of love and prosperity to those who seek it, but do not exist in nature as a result of genetic limitations. White roses have been dyed blue. In 2004, researchers used genetic modification to create roses that contain the blue pigment delphinidin.
Since they do not exist in nature as roses lack the specific gene that has the ability to produce a "true blue" color, blue roses are traditionally created by dyeing white roses. In a book entitled Kitab al-felahah written by Ibn al-'Awwām al-Ishbīlī, which was written in Arabic the 12th century and translated into French by J. J. Clement, being entitled Le livre de l'agriculture, there are references to azure blue roses that were known to the orient. These blue roses were attained by placing a blue dye into the bark of the roots. This process is explained in the aforementioned book and the results have been duplicated by Joret, a prominent scientist in the French community. Nominal "blue roses" have been bred by conventional hybridization methods, but the results, such as "Blue Moon" are more accurately described as being lilac in color.
http://youtu.be/Ohv_4T2k2m0 - Blue Roses | Rare and Exotic | Blue Roses Delivery ( A video presentation)
Blue roses created by artificially colouring white roses.
A Blue Rose from Brazil.
Suntory Blue Rose