Blue is a really interesting color for flowers. It's a question I get all the time. I have a lot of brides who want maybe their something blue incorporated into their wedding flowers, particularly into their bouquet. A request I get quite often actually is for flowers that are blue. As it turns out, there aren't that many flowers that naturally come in blue.
Certainly you don't want to incorporate a dyed flower into your wedding arrangements. I've actually had that question a lot. No, it's not great. It's not good for the flowers. It colors the water. It's not a great option. But, blue flowers do come naturally in, for example, hydrangea. That cornflower blue, really bright blue color hydrangea. Very expensive, but certainly available. Most available in spring and summer. You can get that.
I frankly think with that blue hydrangea, you don't even need to put too many flowers with it. Just gorgeous, few stems of blue hydrangea either in a centerpiece all by itself, just blue hydrangea, or in a bouquet. Blue hydrangea is just the absolute pinnacle. I do get a lot of requests for that.
Then there are some other sort of more delicate wild flowers that are available in late spring, early summer. Tweedia is available, a gorgeous kind of wilder look to that flower. There is a gorgeous color delphinium that comes in a deep blue, a dark blue, and also a light blue in the summer. Most of the blue flowers aside from the hydrangea are going to have that wilder, more unstructured look. If that's the look that you like for your wedding, that's wonderful, but as with all things, really have a collaborative effort with your florist.
The two of you can sit down and sort of look through look books and magazines and online and look for inspiration for blue flowers. Really be open to the notions that you may have to select something just based on what's available for the season. Don't try and convince your florist to dye a flower.