Thinking of Fibonacci

Fibonacci in the Garden—Take 2

Just a couple of Fibonacci thoughts after a weekend in the garden…

Siberian Iris | Image by Joseph D'Agnese

Mystery of the Sixes

Many times I’m asked, “Why do so many flowers have six petals? Six isn’t a Fibonacci number.” Well, it’s true that six isn’t a Fibonacci number, but three is, and many times the flower you’re examining isn’t truly a six-petal flower at all. It is, instead, a three-on-three petal flower. Here’s one of my favorites—the Siberian iris. At first glance, it is a six-petal flower. But then, notice: the three center petals are different from the three outer petals. The dark outer set unfurled first, and set the stage for the lighter-colored inner set of petals. Let that be a lesson to us all. That which appears to be un-Fibonacci sometimes proves to be Fibonacci times two!


Columbine Flowers and Saint Francis Statue | Image by Joseph D'Agnese

Columbine Flowers

These pretty yellow columbine flowers just popped in my garden. (I like to pretend that the little statue is of Fibonacci himself!) Looking closely, I discovered an inner set of five petals and an outer set of five petals. Fibonacci numbers circling Fibonacci numbers...


Flame Azaleas | image by Joseph D'Agnese

Azaleas Yes, Fibonacci No.

These gorgeous flame azaleas used to pop every spring in front of our first house in North Carolina. The old, brittle shrub wasn’t planted in the ideal spot for azaleas, and always struggled in the heat of the summer. But we loved seeing its riotous color every spring.

Azalea flowers typically have 5 petals, which is indeed a Fibonacci number. (This bottom pic of pink ones shows this clearly.) But another source tells me 5 to 7 is the the normal range. This used to make me nuts. Five to seven? Why, oh why, couldn’t it be five to eight, since eight is a Fibonacci number? The answer is, nature does whatever it wants. Statistically speaking, seven is close enough to fall into the Fibonacci range. But you’d have to count a million azalea flowers to chart the results and prove it for yourself...

Pink Azaleas | Image by Joseph D'Agnese

Fibonacci in the Garden

Bunching onion photo by Joseph D'Agnese

This is such a wonderful time of year because there are so many great discoveries to be made in the garden. I spotted these two fun items this past weekend. 

At the bottom is galium aparine, an edible weed that I recognize from my time in Italy, where it’s called “attaccamano,” or “attach-[to]-hand” or “attack-[the]-hand.” In English it’s better known as cleaver, stickywilly, or stickyweed because its leaves cling like Velcro to human skin. (It’s sometimes called Velcro plant.) At my old house I used to find them with whorls of five leaves—a Fibonacci number—but Dr. Internet says six to eight leaves are typical. If you know my children’s book about Leonardo Fibonacci, you know only five and eight are Fibonacci numbers.

At the top is a bunching onion. We planted a bunch of these last spring and forgot to pull all of them up at the end of the season. The onions were dormant all winter and started putting up spiral-shaped seed heads in spring. The onions are still quite delicious, by the way. I’d love to see how far the spirals go, but I am too tempted to pull them because I need space in the garden bed…and because they are so tasty.

Galium acarine photo by Joseph D'Agnese

If you liked this post, you might want to check out the others in the series:

Fibonacci in the Garden, Take 2

Fibonacci in the Garden, Take 3

Learn more about my Fibonacci book for kids here.

Fibonacci: International Supergenius

Blockhead: The Life of Fibonacci by Joseph D'Agnese

I got a box of books the other day containing foreign editions of my children’s picture book, Blockhead: The Life of Fibonacci. Thus far, the book has been translated into four languages: Japanese, Korean, Spanish and Catalan.

Spanish edition.

Spanish edition.

Japanese edition.

Japanese edition.

Korean edition.

Korean edition.

Catalan edition.

Catalan edition.

It’s always a thrill to get these foreign editions and to try to puzzle out the meaning of the words in languages I cannot read.

In this case, I was especially interested in learning how translators made sense of the English word “blockhead,” which Webster’s defines succinctly as “a stupid person.” 

My use of this word in my title and story was deliberate, if a little controversial. In his day, Leonardo openly made use of his nickname, Bigollus, which people today translate as “traveler,” or “wanderer,” or even “dreamer.” 

No one knows what the words really meant in the Tuscan dialect of his day, but I am persuaded that it must have had a meaning close to the modern Italian word, “bighellone,” which means “dunderhead” or “absent-minded” or “idler” or “loafer.”

While some writers on the Web persist in saying that Leonardo’s name must have been a way for his neighbors to praise this well-traveled man, I say they probably haven’t spent much time in Italy. It seems entirely in character for small-town paisani to openly mock a well-educated math genius for being an absent-minded professor type. At least, that’s my story, and I’m sticking to it. 

Since I can’t read the Korean or Japanese editions, I’m setting these aside to share with a few friends who can help me out. 

But since I can muddle through in Spanish and Catalan, I was please to see that these editions translate the “Blockhead” of the title as “Sonador” and “Somiador” respectively. Both words mean “dreamer.” 

The title of the book in these two languages of Spain is therefore “Fibonacci: The Dreamer of Numbers.” Both are published by Barcelona’s illustrious Editorial Juventad, whom I thank profusely.


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Fibers & Fibonacci: The Return!

Fibonacci potholders.

Fibonacci potholders.

Here’s more of my exchange with the leader of a weaving camp for kids. Above and below are shot of the creations the children made using the Fibonacci Sequence...

Dear Joe,

Heritage Weavers & Fiber Artists have just completed a 2nd week of Fibers Arts Camp for Kids using Blockhead, the Life of Fibonacci as the focus. You would have enjoyed the closing ceremony where the campers demonstrated the activities they learned. They explained the concept of Blockhead, the Life of Fibonacci, and demonstrated how they used the sequence to plan both the potholder project and the width of stripes used in weaving a book bag. 

Fibonacci book bags.

Fibonacci book bags.

 I am including 2 pictures this time—more potholders (top) and a picture of the finished book bags (below).  Using the sequence for proportion of the stripes seems to make any color combination pleasing to the eye.

 We will look forward to meeting you at your next book signing in our area.

Ruth Howe, HWFA Camp Director


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Fibers and Fibonacci

Fibonacci potholders.

Fibonacci potholders.

I am constantly learning new uses for the Fibonacci Sequence, and ways that people in different professions use these remarkable numbers. I recently corresponded with a woman who runs a fiber arts camp for children near my home in North Carolina. Above is a shot of the creations the children made using the Sequence. Here’s what the teacher told me about it.

This is a picture of the potholders made at the Fiber Arts Camp hosted by Heritage Weavers & Fiber Artists last week at Johnson Farm in Hendersonville, NC.  The Fibonacci Sequence is used with one looper of color 1, two loopers of color 2, three loopers of color 3, and five loopers of color 4, and reversed—1, 2, 3, 5, 3 ,2, 1—and then is woven in the same sequence. 

As weavers, we find using the proportions of the Fibonacci Sequence are always pleasing to the eye, no matter what combination of colors are used.

 Thank you for an inspiring book... 

Ruth Howe, Camp Director

The Korean edition of Blockhead is here!

Korean edition of the children's book, Blockhead: The Life of Fibonacci, by Joseph D'Agnese

The morning mailbag brought this Korean edition of my children’s picture book.  I can’t read a word of this. I wonder how the word Blockhead translates into Korean. Anyone know? Is it insulting? (It should be.) Is it hilarious? (Hope so.) Next up: Spanish and Catalan versions.

Meanwhile, on our shores, this book e-tailer is making the English version of the book available for the ridiculously low, low price of $5.99. Read the fine print. The books are bookstore return copies, and may have a bit more wear than pristine copies you get new. But they should still be fine for classroom use.

Only 12 copies left...


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Sing the Fibonacci Song, Won't You?

Tripping down memory lane with remarkably spry, 800-year-old Fibonacci (seated, in blue gown).

Tripping down memory lane with remarkably spry, 800-year-old Fibonacci (seated, in blue gown).

I was in Washington, DC, today to visit with students at the Georgetown Day School. We had a blast, and the kids were among the most knowledgeable Fibonacci fans I’ve ever encountered. And no wonder! It turns out that for the last 13 years, this school has celebrated a Fibonacci Day, where they talk about all things Fibonacci.

Sometimes, they are lucky enough to have a visit from the old Maestro himself, Leonardo Fibonacci, played by a hilariously comic teacher by the name of Reed Thompson. Fibonacci and I riffed on the building of the Leaning Tower of Pisa, which happened when he was a boy. We talked about him taking that exciting trip to Algeria that started him on a lifetime of loving numbers, And we talked about the superiority of Hindu-Arabic numerals over Roman numerals.

This is your life, Fibonacci!

This is your life, Fibonacci!

It was a dream come true. And then, at the end, the kids and I serenaded Maestro Fibonacci with a song the children had prepared for the occasion.

The song appears here with the kind permission of its author, Georgetown Day School teacher Barbara Buonora. Please do not reprint it without contacting the school for permission. But you are free to belt it out at the top of your lungs!

The song is sung to the tune of “My Darling Clementine.” My thanks to Fibonacci, MaryLou, Rose and everyone else who made it such a memorable day.

The Fibonacci Song

Leonardo Fibonacci

Born in Pisa, Italy—

Most Talented Math’matician

In Middle Ages history!

1, 1, 2, 3,

5, 8, 13, 21, and 34

55 and 89,

One hundred 44!

These are just his infinite sequence—

Patterns found in sunflower,

And in pinecone, shell and pineapple,

Music, art, and even more!

Leonardo loved his numbers

And we love them, too, you see,

For without them, life is boring—

Thank you  Fibonacci!


“The Fibonacci Song,” copyright 2004 by Barbara Buonora, Georgetown Day School. Used with permission. All rights reserved.


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Blockhead is a "Best Children's Book of the Year"

Bank Street College Logo

Just found out that my children’s picture book, Blockhead: The Life of Fibonacci, about the Medieval mathematician Leonardo of Pisa, was picked one of the Best Children’s Books of the Year by the Bank Street College of Education. Great news coming from an institution that has trained so many fine teachers in New York City.


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Fibonacci Phlox

Phlox image by Joseph D'Agnese

Chillier here today after a massive thunderstorm last night. But these little guys hung in there. They are Emerald Pholox (“phlox subulata”) which display Fibonacci 5 in their petals.

I have not spotted any flowers that show six or four, so I think the number is pretty consistent across the board for the cultivar.

If I had to pick a flower to plant now to share later with kids, I’d pick this little guy. Fun selection for a Fibonacci garden...


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Fibonacci Vinca

Vinca vine image by Joseph D'Agnese

Vinca vine flowers display a Fibonacci 5 configuration, one of the most prevalent numbers in the plant and animal kingdom. (Think starfish, apple seeds, etc.)

These pale blue flowers are blooming now in our area. I like the asymmetrical cast of the petals, which give them a slight sense of movement. They look a little like a child’s pinwheel, designed to catch the wind.


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