In the absence of icy snow and oppressive heat, I have had to rely on more subtle signs to discern the changing seasons. When I lose my sense of time, I use a single gingko tree I pass every morning on my way to work as a nudge. For most of the spring, it is light green, like chartreuse. In the summer, the green deepens. In the fall, the leaves fade to yellow and slowly brighten to a blazing citrus. Each fan then drops slowly, slowly ... littering the ground with tiny flames, twinkles of brightness ... until the tree becomes bare to announce that winter has arrived.I have turned many years using this gingko-tree calendar.
Photo courtesy of Kew Gardens, England.