Usually associated with sadness it is however arguable that BLUE is the most important colour in the garden, always ignoring the green of the foliage of course.
It is the only colour which goes with any other colour, whether hot reds, oranges and yellows, or the cooler pinks, lilacs etc., not to mention white or green as well.
Some people maintain that there aren't many true blues in the garden! However we shall see.
Which "blues" are important to you?