{Plants} : petals

The numbers of the Fibonacci sequence and the Fibonacci sequence itself occur frequently in plants.  The patterns of leaf growth on branches are related to the Fibonacci sequence, as are the double spiral patterns of seeds on sunflowers.  The surface areas of artichokes, pineapples, and pinecones are covered by “scales” arranged in patterns related to the Fibonacci sequence.  Perhaps the simplest example of the Fibonacci sequence in nature can be found in flower petals: in many flower species the number of petals on a blossom is a Fibonacci number.

Trillium - 3 petals
Wild Rose - 5 petals
lower/bloodroot.htmlBloodroot - 8 petals
Black Eyed Susan - 13 petals
Chamomile - 21 petals
Gaillardia - 34 petals petal images, various sources, see bibliography.

The above are just a few examples of flowers with a Fibonacci number of petals.  Others include enchanter’s nightshade, buttercup, delphinium, columbine, aster and daisy.  Some of these flowers always have the same number of petals, but some, such as daisies, can have either 13, 21, 34, 55, or 89 petals.

Continue upwards in the tree: {# of Elements} {2-D Spirals}

Sources: Koshy, Thomas. Trillium, <framesandartbykluttz.com>; Wild Rose, <timetotrack.com>; Bloodroot, <wiseacre-gardens.com>; Black-Eyed Susan, <gis.net/~twhelan>; Chamomile, <thewildrose.net>; Gaillardia, <colorwithplants.com>. See biboliography.