Purple is such a gorgeous color, and it's universally flattering. With flowers, in every season you have purple flowers available. So purple is a really good choice when thinking about wedding flowers, either for centerpieces or for bouquets.
A look I really love is to do purple in a whole, wide ombre spectrum, to do purples in everything from very light lavender purples all the way down to a rich, almost black purple. You will find a whole, wide variety of flowers in purple that can help you with this process.
For example, in a lavender, you can have actual lavender that you gather together and have sort of to provide texture in an arrangement or a bouquet. You can have lavender roses, lavender lilies, anything kind of sweet and delicate. Grape hyacinth comes in lavender, really, really beautiful.
Then all the way down to that dark black spectrum. Black calla lilies, we call them black, but they're really a deep purple or magenta color. They can really add a beautiful depth to a bouquet or an arrangement.
So think about flowers even if you have a particular color picked out, like purple, think about doing a wide range or a spectrum of those colors in that hue. You'll really be pleased, I think with the results.