by Doreen Sandor 


(Note - see assignment at bottom of webpage.)

Fibonacci number patterns occur so often that we often hear the phenomenon referred to as a "law of nature".  

If we examine flowers, we would find that the number of petals on a flower is often one of the Fibonacci numbers.   For example:

White Call Lily -  1 Petals

Euphorbia -  2 Petals

Trillium - 3 Petals

Columbine - 5 Petals

Bloodroot - 8 Petals

Black-Eyed Susans - 13 Petals

Shasta Daisies - 21 Petals

Ordinary Field Daisies - 34 Petals

"Fibonacci Numbers in Nature" - Images' Source:

One- and two-petalled flowers are not that common.   Three- and five-petalled flowers are more common, and there are quite a number of well known species with eight petals.    Thirteen-, twenty-one, and thirty-four-petalled flowers are also very common.    I'll bet you never thought how much the number of petals differed on flowers, and now we can see that there is a relation between the number of petals these flowers have - the Fibonacci sequence! 

The association of Fibonacci numbers and plants is not restricted to numbers of petals.   Dr. Jill Britton's website explores more nature connections to the Fibonacci sequence:

Fibonacci numbers can also be seen in:





Source of Images:  Knott, R.. "The life and numbers of Fibonacci ." The life and numbers of Fibonacci . Millennium Mathematics Project. 27 Aug 2006 <>.


If you cut a fruit or  vegetable you will often find that the number of sections is a Fibonacci number:   

have 5


Bananas have 3

Source of images and Information: "Plants." Phi - The Golden Number. 27 Aug 2006 <>.



Nature Research Task:

With your parents' permission, find two fruits or vegetables in your home.  An Alternative would be to examine a flower as one of your items.   Use an index card to record your results.  These will be posted later on the Fibonacci Blog.

For a Banana:
 Count how many "flat" surfaces it is made from - is it 3 or perhaps 5?    

With your parents' assistance peel the banana and then cut it in half (as if breaking it in half, not lengthwise) and look again. Surprise! There's a Fibonacci number. 

For a Cauliflower or Broccoli:
First look at it.  
Count the number of florets in the spirals on your cauliflower. 
The number in one direction and in the other will be Fibonacci numbers, as we've seen here.

take a closer look at a single floret (break one off near the base of your cauliflower).   It is a mini cauliflower with its own little florets all arranged in spirals around a centre.   

If you can, count the spirals in both directions. How many are there? Counting them again shows the Fibonacci number.

For a Flower:
What is the name of the flower?  Note if the number of petals is a Fibonacci Number.   How about the number or organization of leaves?  The seeds?  If possible, find an image of the flower online and post it as well. 

Post details about your investigation your  notes on the Fibonacci Blog.  Share your observations with your classmates.    Then respond to at least three (3) fellow classmates' postings, using Grade 4 ELA standards.   

Due Date: Tomorrow a.m.