Gardening: The Joy of Sunflowers

August 6, 2010 | Story by: Hal Goodtree | Categories: Featured, Gardening

Story and pictures by Hal Goodtree.

Cary, NC – It’s sunflower time of year here in the Triangle. And while this summer’s heat has put a hurting on everything from corn to zinnias, lots of happy clumps of sunflowers are evident around town.

About Sunflowers

The first thing to know about sunflowers is that they’re so easy to grow. Just pop some seeds in the ground in early summer and keep it well-watered. In just a few weeks, your efforts will be satisfied with a plant taller than many children.

According to Wikipedia:

Scientifically, sunflowers (helianthus) are annual native to America. The giant flower heads are actually made up of many smaller flowers. According to Wikipedia:

What is usually called the flower is actually a head (formally composite flower) of numerous florets (small flowers) crowded together. The outer florets are the sterile ray florets and can be yellow, maroon, orange, or other colors. The florets inside the circular head are called disc florets, which mature into seeds.

The florets within the sunflower’s cluster are arranged in a spiral pattern. Typically each floret is oriented toward the next by approximately the golden angle, 137.5°, producing a pattern of interconnecting spirals where the number of left spirals and the number of right spirals are successive Fibonacci numbers. Typically, there are 34 spirals in one direction and 55 in the other; on a very large sunflower there could be 89 in one direction and 144 in the other.^[1][2][3] This pattern produces the most efficient packing of seeds within the flower head.^[4][5][6]

Sunflowers most commonly grow to heights between 5–12 ft. Scientific literature reports that a 40 ft, traditional, single-head, sunflower plant was grown in Padua in 1567. The same seed lot grew almost 26 ft at other times and places, including Madrid. During the 20th century, heights of over 25 ft have been achieved in both Netherlands and Ontario, Canada.

Just for the record, I have never grown a 40 foot sunflower.

Sunflowers Around Town

We must have thousands of sunflowers growing around town. This makes for a seriously happy gold finch population.

Here are three of my favorite sunflower spots in town. One’s a gas station, one’s a farm and the last is a huge field of sunflowers hidden behind a neighborhood.

Got Garden Pictures?

If you’ve got garden pictures of what’s growing right now, post them in the story comments, on Facebook or the Cary Flickr Group.