Even in her darkest moments, Helen Keller always knew how to find the light. She advised, “Keep your face to the sunshine and you cannot see the shadow. It’s what sunflowers do.”

Sunflowers are known for their sunny disposition. These plants are heliotropes, meaning that they follow the path of the sun across the sky. In truth, sunflowers only do this when the plants are young. Once the flowers are mature, they do not follow the sun, but generally face east. Their scientific name, Helianthus, literally translates to ‘sun flower.’

A universally loved flower, sunflowers are identifiable to just about everyone. Symbolizing adoration, loyalty and longevity, sunflowers invite happiness as well as inspire poetry. William Cullen Bryant eulogized their late-season presence and eventual decline in his poem The Death of the Flowers:

   “But on the hill the goldenrod, and the
aster in the wood,
    And the yellow sunflower by the brook
in autumn beauty stood,
    Till fell the frost from the clear cold
heaven, as falls the plague on men,
    And the brightness of the smile was
gone, from upland, glade, and glen.”

Botanically, sunflowers can be any of about 70 species of flowers in the genus Helianthus and family Asteraceae. The sunflower most recognized is the common sunflower, but there is one southern variety, whorled sunflower, that is so rare that it was put on the federal Endangered Species list in 2014.

The structure of the sunflower invites inquiry. While there can be one or multiple large flower heads, these are, in fact, many smaller flowers called florets. Each floret has the ability to produce one seed, and collectively one head can have up to 2,000 florets that will become seeds. 

And in a curious quirk, there is a pattern to the floret (and seed) placement. Fibonacci explains it all! The Fibonacci sequence of numbers, in mathematics, describes a pattern where each number is obtained from the sum of the two proceeding. In the case of the sunflower, the number of seeds is a Fibonacci number. To add to the mystery, the location of the seed is also predictable and is based on something called the “golden angle.” The golden angle is 137.5 degrees and produces a pattern of interconnected spirals, each radiating from the other at that angle. Other natural objects that share this Fibonacci effect include pinecones, whorled shells and spiral galaxies.

If you are lost with the math, soldier on and consider another of the unique traits of the mighty sunflower. Research has shown that growing sunflowers can eliminate toxins such as arsenic, lead and even uranium. At both Chernobyl and Fukushima, sunflowers were employed to reduce toxins released by both disasters.

Sunflowers are also valued for food, medicine and even their fiber. Stalks have been used for building, and yellow and purple dye can be extracted to color fiber or for body paint. Perhaps more valuable than the plant itself is a Vincent Van Gogh sunflower painting that sold for more than $39 million in 1987.

Though inspiring high prices, sunflowers can also be high in stature. The current height record for this flower is just over 30 feet. It can also be small, though, with that honor held by a small sunflower just over two inches. And that classic yellow flower can also be red, orange, gold, brown or purple.

Regardless of their size, color or use, the sunflower has found its place in our world. Henry Ward Beecher explained the intersection of folks and this flower. 

“Flowers have an expression of countenance as much as men and animals. Some seem to smile; some have a sad expression; some are pensive and diffident; others again are plain, honest and upright, like the broad-faced sunflower.” 

I think Helen Keller would have liked that quality in sunflowers: “Never bend your head,” she wrote. “Hold it high. Look the world straight in the eye.”

Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown, and author of Martha’s Vineyard: A Field Guide to Island Nature.