1. Flowers with 1 petal (very rare)
White Calla Lily
Lilies have 6 petals;
Fusing of petals

2. Flowers with 2 petals (very rare)
Euphobia

3. Flowers with 2 petals (very rare)
Can still be found in Singapore: photo taken outside a HDB flat

4. Flowers with 3 petals (quite rare)
Waterplantain
Trillium

5. Flowers with 5 petals (very common)
Hibiscus
Taken in Singapore

6. Bougainvillea: which one is the flower?
Pink ‘flower’: 3 bracts or modified leaves;
light-yellowish flower in centre has 5 petals;
actually there are 3 flowers in centre

7. Columbine: How many petals?
5 petals & 5 sepals (modified petals)
Most of the times, sepals look exactly like petals

8. Daffodil: How many petals?
3 petals & 3 sepals (modified petals)

9. Flowers with 8 petals (quite rare)
Yellow Moonbeam Coreopsis
Bloodroot

10. Daisies with 13 petals (quite rare)
Black-eyed Susan
Orange Zinnia

11. Daisies with 21 petals (quite rare)
Shasta Daisy
‘Petals’ are bracts or modified leaves;
flowers in centre;
Composite Flower

12. Daisies with 34 petals (quite rare)
Field Daisy
White Daisy

13. Flowers with 34 petals (quite rare)
Sunflower
‘Petals’ are bracts or modified leaves;
flowers in centre;
Composite Flower

14. Exceptions
Ixora
Daylily

15. Exceptions
Starflower
Passion Flower

16. Exception Type 1
Some flowers follow Lucas Sequence: 2, 1, 3, 4, 7, 11, 18, 29, …
Like Fibonacci sequence except first 2 terms are 2 and 1, instead of 1 and 1
Fibonacci: 1, 1, 2, 3, 5, 8, 13, 21, 34, …
E.g. 4 petals and 7 petals

17. Flowers with 4 petals
Ixora: Taken in Singapore

18. Flowers with 7 petals
Starflower

19. Exception Type 2
Doubling of the petals: e.g. from 3 to 6 petals; from 5 to 10 petals

20. Flowers with 6 petals Daylily 3 petals & 3 sepals
We just use layman’s term: 6 petals. Why?
Or else problem with daisies and sunflower

21. Flowers with 6 petals
Iris
3 petals & 3 sepals

22. Orchid: 6 petals Singapore National Flower Vanda Miss Joaquim
2 petals, 3 sepals, 1 lip (modified petal)

23. Orchid: 6 petals Learn more about Singapore National Flower:

24. Orchid: 6 petals
NTU’s own flower: Dendrobium Nanyang

25. Orchid: How many petals?
2 petals & 3 sepals?
Lip not obvious or no lip (hybrid)

26. Flowers with 10 petals
Passion Flower
Probably 5 petals & 5 sepals

27. Exception Type 3
Mutations and hybrids that have been created artificially also account for exceptions

28. Marsh Marigold: 5 or 6 petals?
The 6-petal flower is a mutant

29. 4 or 5 petals?
Taken in Singapore
The 4-petal flower is a mutant

30. Roses: How many petals?
Hybrids: many petals

31. Wild Roses: How many petals?

32. Are you sure there is a pattern?
Fibonacci: 1, 2, 3, 5, 8, 13, …
Lucas: 4, 7, 11 (we haven’t seen 11 petals)
Doubling (even nos.): 6, 10, 12, 14, 16, … (we haven’t seen 12, 14, 16, … petals)
Petals: 1-8, (cover most numbers!)
If can find 9 or 15 petals, this is rubbish!

33. So where is the Fibonacci pattern?
The Fibonacci pattern comes mainly from daisies: 13, 21, 34, 55 or 89
Botanists may disagree because some ‘petals’ are actually sepals or bracts
But we go by what we laymen see. Why?

34. So where is the Fibonacci pattern?
E.g. if nature has fused the 3 petals and the 3 sepals of the White Calla Lily into 1 petal, why call it 3 petals?

35. The Internet Search for 9 Petals…
Marsh Marigold: “5-9 deep yellow petals”
But mostly 5 petals
6-petal is a mutant
“5-9 sepals; no petals”
Website can be wrong

36. The Internet Search for 9 Petals…
Lesser Celandine: “5-9 yellow petals”
But mostly 8 petals
Website can be wrong or the rest are mutants

37. The Internet Search for 9 Petals…
Mayapple: “6-9 petals”
But mostly 6 petals
Website can be wrong or the rest are mutants

38. The Internet Search for 9 Petals…
Royal Ramparts: “9 deep red-purple petals”
Japanese Iris Nursery
Probably a hybrid

39. The Internet Search for 9 Petals…
Áashild Kalleberg: “8-9 petals & 3 sepals”
Website says it is a hybrid
Some sites on dried flower arrangements
Conclusion: Flowers with 9 petals are either mutants or hybrids
Websites are not always reliable

40. Websites on Fibonacci Numbers
ccins.camosun.bc.ca/~jbritton/fibslide/jbfibslide.htm (contains other patterns as well)
library.thinkquest.org/27890/applications5.html

41. How many ridges in a banana?
Hint: It is a Fibonacci number
ridge