Dahlias: the jewels of the late summer garden. Shades of red, yellow, orange, pink, with their petals forming intricate geometric structures. But, like roses and many other flowers, the dahlia spectrum is missing one colour: blue. So why are blue blooms so rare in nature?
April 23 is Saint George’s Day, celebrated in particular by a number of countries and cities where Saint George is the patron saint. One of these is, of course, England, though here the celebrations tend to be quite muted and minimal, and certainly nothing in comparison to the merriment that heralds St Patrick’s Day. In Catalonia, however, it prompts a good deal more in the way of celebration, and I made this graphic for the Institute of Chemical Research of Catalonia to illustrate some of its facets.