Count Your Sunflower Spirals - and Fibonacci and Lucas Sequences

I'm continuing research for a presentation on Seeing Math Patterns in Nature - and I am looking at growth patterns in sunflowers and other plants.

Sunflower - photo by Mary Van Dyke

Current estimates are that 90% of plants follow the Fibonacci sequence: (1 1 2 3 5 8 13 21 34 55 89... ) for optimum flow of auxin, the plant growth hormone, and evolutionary adaptation to maximize efficiency in packing seeds.

Here's Ron Knott's diagram of a 1000 seedhead sunflower with 89 and 55 spirals at the perimeter:

Some plant species, such as sunflowers, can follow both the Fibonacci and other sequences such as the Lucas sequence (1, 2 3 4 7 11...) - and other permutations of series too.

A big global citizen science experiment to study sunflowers and count their spirals has been running since 2012 in honor of mathematician Alan Turing's "enigma code breaker's" 100th anniversary of his birth - and the discovery of his unfinished work on the math of sunflowers.
See Turingsunflowers.com.

In 2012 people around the world planted sunflowers and counted their spirals - here's how from the Geeky Gardener - Anna Evangeli.

Fibonacci V Lucas: spot your sunflower's spiral › Science Features (ABC Science)

From the initial big data experiment of Turing's Sunflower Project - results came from 557 sunflowers from 7 countries as follows:

• Fibonacci spiral sunflowers - 458
• Lucas spiral sunflowers - 33
• Double Fibonacci sequence numbers sunflowers - 26
• Other spiral numbers - a small number of sunflowers with no apparent Fibonacci or Lucas number patterns

How about counting the spirals of the sunflower seedheads you planted in your garden this year?
Or do you plan to plant some sunflowers to count next year?

Collecting Sunflower Seeds - photo by Mary Van Dyke