Color in the garden is nice as long as we can see it. There is not so much to see after the sun goes down. That is why some gardens that get used at night are illuminated.

Sometimes it is important to illuminate walkways, driveways and stairways for safety, even if exhibiting the landscape is not important. For such applications, the quality of the light is not as important. Sodium vapor light that works so well for street lamps can make plants look rather sickly. Mercury vapor lamps can make them seem rather pale and bland. Modern LED lamps just look creepy.

So, what happens when foliage that already looks sickly get illuminated by light that enhances the sickly appearance? Well, like many styles of contemporary art, it is a matter of taste . . . or perception . . . or some other big word that a horticulturist neither…