There are versions of white that do not sunburn much at all. It is very hard to generalize about white flowers as the reason they are white can result from at least 5 major chemical formations. All dahlias are white is a correct statement. What happens to the white pigment as it matures is what creates all the other colors of dahlias. In a way, it is like mixing paint pigments with white pigment. A tiny dab of red and yellow may make a pale apricot. Unlike the painter, you do not get to mix the paint until it is just right as you have to breed many flowers that might have the right combination and hope one has the color. In our pale apricot sport, it appears that it suffers from not enough pigment as opposed to the wrong pigments. So why are "pastel" colors rare in dahlias? Maybe it is the burn factor. If there are 5 versions of genetically white flowers and three of them burn easily if they remain white. If you add some "apricot" pigment to the burning flower, it still burns. If you add the apricot pigment to one of the other two, it does not burn as much. By the way, "apricot" is not a specific dahlia pigment and it may be much more complicated than what I am proposing. Some dahlias start out as white dahlias and then go on to become yellow dahlias and then the yellow is covered by some "red"(not apricot) pigment that when combined with the yellow may be apricot. I believe that an oil painter can mix white, red an yellow and get apricot. So are pastel colors more difficult to breed? It has been said that good white flowers are hard to breed. Now you say let's breed a good white flower that has a slight amount of apricot pigment. So it appears to me that breeding pastel colors can be more difficult than breeding white flowers. Having said that, many or most of the pastel color dahlias that have been introduced fade easily and no one appears to care. So really, they can be bred more easily.
