Good Day, Sunshine

Writer Michael McLeod explores the backstory of a showy bloomer.

Once there was a nymph who had a crush on Apollo. She couldn’t keep her eyes off him. But he was the sort of guy who thought the sun rose and set on him. Which, in all fairness, it did: He was, after all, the god of sunshine.  

 So there was no way this was going to work out for the nymph. The other gods took pity on her, though, and decided to give her a break. If you can call being turned into a big yellow flower a break.  

 And that, assuming you consider Greek mythology a trustworthy source of botanical information, is the story of how the sunflower came to be. 

Every plant worships the sun, but Helianthus is its most unabashed admirer. Its blooms not only look like the orb’s blazing rays but track its course across the sky like satellite dishes homing in on a signal. Perched high atop shifting stalks, they appear to crane their necks over the course of the day. Morning finds them facing east, patient as pets awaiting their owners, and by sunset they’ve swiveled to face the ebb of the day. 

It’s called heliotropism: the tendency of plants to turn toward the sun to maximize photosynthesis. The sunflower didn’t invent the strategy, but pursues it with a twist. The secret is in the stem. During the day, one side of a sunflower stem elongates, tilting the bloom one way. At night, the other side of the stem takes over, growing ever so slightly to tilt it back. Rinse, repeat. Et cetera, et cetera. The nymph never wavers.  

The Greeks may have been the first to see it that way, but they certainly were not the last. Centuries later, the Irish poet, Thomas Moore, would write:  

No, the heart that has truly loved never forgets, 
But, as truly, loves on to the close, 
As the sunflower turns on her god when he sets 
The same look which she turned when he rose!

Categories: Gardening