Did you know, for instance, that most daisies have 34, 55 or 89 petals? Those numbers should be familiar to you; they are the 9th, 10th, and 11th Fibonacci Numbers. Have you ever wondered why four-leaf clovers are so rare? It's because four isn't a Fibonacci Number. Here is a list of flowers with number of petals:
Number of Petals Flower
3 petals (or 2 sets of 3) lily (usually in 2 sets of 3 for 6 total), iris
5 petals buttercup, wild rose, larkspur, columbine (aquilegia), vinca
8 petals delphinium, coreopsis
13 petals ragwort, marigold, cineraria
21 petals aster, black-eyed susan, chicory
34 petals plantain, daisy, pyrethrum
55 petals daisy, the asteraceae family
89 petals daisy, the asteraceae family
There are exceptions to this list. Most fall into two categories; a doubling of the number of petals, and/or a version of the Fibonacci Series called the Lucas Series (2, 1, 3, 4, 7, 11, 18, 29, 47, 76, etc.). Mutations and variations from species to species also account for exceptions but when the number of petals are averaged, the number will usually be a Fibonacci or Lucas Number.
Source:Online Resource