The breeders have done a lot to get a variety of colors and markings and forms that extend what nature provides through selective breeding. But they can't produce a color like true blue that does not exist in nature. There are very few orchids of any sort that are really blue (the so called "blue" color is coerulea, more of a blue-violet) and the ones that do have the genes for that color are not related to Phals so won't breed with them.