Thursday, June 17, 2010

Designed for Pollination

I recently mentioned in a post Asarum canadense, the North American native perennial known as wild ginger, a favorite woodland groundcover of mine. It encouraged me to go and find a patch of it and see if I could find a flower to photograph.

You see, in nature and in horticulture you have to remember that plant design has nothing to do with us and our wants, it all has to do with the species' partner in crime, it's pollinator. For all species of living things the greatest and most vital challenge ingrained, whether conscious or not, is to keep our species alive, to reproduce. It's why we marvel so at the presence and creation of life. In my opinion it's why humans developed an abstract mind, to overcome living in challenging climates and keep our species alive in the face of environmental challenges. Of course now our imaginations have gotten us into a heap of trouble in the other direction because we have so manipulated our own environment, but I'm not going to get into that now. But clearly Darwin was right on! Mutation and variation and natural selection are genius aspects of life, mind blowing in fact. Enter the wild ginger. Over the course of it's evolutionary lifetime Asarum canadense has come to be beetle pollinated. Therefore the flowers are not tall and flashy, in fact they are just the opposite. The flowers lay on the soil surface among the fallen twigs and leaf litter. They have all the basic parts of a flower, but a thing of beauty? Well I guess that falls to the eye of the beholder, doesn't it...? The outside of the flower tends to be white and fuzzy, perhaps resembling a mold or fungus that would grow on something rotting. Past the green petals the center of the flower is red and smells of carrion, the perfect lure for a beetle thinking it has found the ideal morning snack. The beetle enters, and finding no nourishment leaves and continues on his search, but not without gaining some pollen deposits on it's body. To the next flower he goes, sure that one might have what he is looking for. Accidentally drop off a little pollen, pick up some more, and we have pollination! Alas he is misled again, and so continues his woodland search. Reproduction begins and a species thrives. All thanks to something that most people will never think to look for, this little guy.

In the same vein have you ever thought about why some plants have white flowers?
It's a question I love to pose to people because in many cases they realize that they have no idea why a given flower, like this Hydrangea for example, is white instead of another color. They could be blue or pink or any other myriad of colors, but white, why white? might begin to see where I am going with this.
Now that it is summer and the nights are warm I have a suggestion. The next time there is a full moon and the sun has set, go for a walk. What you will see is that the white flowers show up best in the landscape, present and inviting even in the dark. For it is often at night that pollinators like bats and moths will come out of hiding and visit their showy, fragrant friends. Look up "moonlight gardens" and you can learn about fabulous nighttime blooms and be introduced to a whole new side of garden design. Hopefully you will be pleasantly surprised about the amount of activity in the nighttime garden as I once was.
And then when you visit your nighttime garden again in the future look at those old, past flowers. White hydrangeas in our back yards tend to fade to a dull pink color, much like the lotus flowers blooming continents away, but what is the connection? Upon pollination the flower has done what it has been asked to do, for seed will soon be developed and reproduction is underway. The flower changes color because it no longer has to attract a pollinator, or use the energy to stay that glowing white, and it can fade comfortably into the landscape. The pollinator passes by the now uninviting flower, knowing it is not worth stopping by, it's too late. I remember learning that in horticulture school and loving it. So smart, this world around us. ...and nothing to do with us at all!

1 comment:

JayLeigh said...

Oh, this is so cool! I didn't know about this! I've told my children now, and I'm hoping we can start a moonlight garden. :D