“The flower is the poetry of reproduction. It is an example of the eternal seductiveness of life.” Jean Giraudoux
I came upon an all-encompassing book on the whys and wherefores of plant color – Nature’s Palette; The Science of Plant Color written by David Lee, a botanist at Florida International University. I was curious about how flowers get their color. Lee probably shared a little more than I wanted to know, but still he thoroughly and scientifically explained the mystery of color and even admitted that some of it cannot yet be explained. For instance, green color normally comes from chlorophyll, but not always. The jade vine from New Guinea has a bright blue-green corolla that is from some other mysterious combination of pigments. Most flowers of course are not green simply because the purpose of petals is to attract pollinators with contrasting color that stands out against green leaves.
So the colorful petals often serve as landing pads for birds, bees, butterflies and even bats and carrion loving flies. The center sex organs, the male stamen and the female pistil, are usually contrasting in color. Might as well advertise.
Butterflies like bright flowers in the yellow to purple range. They don’t need to be fragrant but must be open during the day. Bats, in contrast, prefer pale flowers that are musty smelling and open in the evening. Moths pollinate sweet-smelling flowers like tuberose, jasmine and gardenia. Birds, not having a well-developed sense of smell, don’t look for fragrance but search out bright red tubular flowers with lots of nectar. For every flower there seems to be a favorite suitor.
Lee uses orchids to explain flower color, but I’m interested in the flower color in my garden. A favorite bedding annual I grow is lantana, a member of the verbena family. They’re so dependably perky, blooming all summer and into frost. The fact that they change color through the season is not because they’re contrary. Unpollinated flowers start out yellow to attract their favorite pollinator – the thrip. Thrips like yellow. After pollination the flowers darken to orange and red, which the thrip doesn’t favor. They’re done with him, so they close up shop to thrips. How practical. All this is explained online at Gardening Know How.
In the last paragraph of his book, Lee makes a heartfelt case for caring about the natural world.
“Unscientifically, the strongest reasons for preserving green landscapes, whether as wilderness, a patch of wildflowers by a road, or small garden in a housing development, are really emotional… Perhaps the best that I can do as a scientist is to reveal this beauty to those unaware, or in ways not yet appreciated, to increase knowledge, appreciation, and – ultimately – a feeling for plants. Despite the political and environmental problems we face, we still live in an awesomely complex and beautiful world, mirrored by the colors with which plants illuminate our lives.”