Are you a fan of the color blue? Blue is thought to symbolize commitment and tranquility and is one of the more recently popular colors for weddings, so if you're a fan you're in luck. While the color blue may occur less frequently in the world of flowers, there are still gorgeous blue flowers you may want to consider for your wedding.
Blue Thistle
Often overlooked, blue thistle is a unique and interesting touch to add blue in any arrangement or bouquet. While it's technically a weed, its unique beauty and somewhat prickly texture make them the perfect companion to flowers. They are strong and sturdy making them ideal for boutonnieres and corsages, and they dry very well if you're into dried flowers.
Blue thistle is used as a filler in bouquets and arrangements, and as a companion to flowers in boutonnieres and corsages. It looks best when paired with white flowers for an elegant look and with orange and burgundy for a fall-time look.
Delphinium
Blue delphiniums are available in dark and light shades. Delphiniums are often used to add a bit of height and their blooms can be cut and used for corsages and boutonnieres as an accent flower. They can also be used in arrangements for some added height and in bouquets to break up an otherwise too round/compact shape and add some angles. 
We've used delphiniums as a dramatic touch in flower clusters for arches like above where the bride wanted an enchanted fairytale theme. For this, we used the lighter shade of blue delphiniums and had a palette that was a mix of blue and white.
Hydrangea
Though the blue color is pricier than white or green, blue hydrangea is worth every penny. This stunning shade of blue is an eye-catcher due to the sheer size of the hydrangea stems. Hydrangea is best used as a filler in centerpieces and in flower clusters for an arch.
We used blue hydrangea in this same arch as above. In this close-up shot below, you can better see the gorgeous powder blue shade it came in.
Tweedia
Another filler flower, tweedia is a small bloom in a brilliant blue shade. Native to Brazil, tweedia is vine-like and best used in pops in arrangements and bouquets. It looks stunning in a bouquet with contrasting sizes and textures such as Queen Anne's lace for a wildflower bouquet, and anemones for something more sophisticated.
Cornflower
If you are looking for a flower with a vibrant shade of blue, cornflower is the perfect fit. These small button-like blooms are best if you desire a wildflower aesthetic and look greatest in a bright color palette with yellows and reds. They can be used in arrangements and bouquets as a filler flower, and in corsages and boutonnieres as the main flower.
Nigella
Like the cornflower, nigellas have a wildflower look and look great in a wildflower arrangement, however, they also pair well in a more refined aesthetic where they add a varying texture. Fun fact, they are also referred to as "love-in-a-mist" because of the foliage that grows and clouds around their heads.
Bunny Tails
If you don't mind a touch of dried flowers, bunny tails can add that touch of blue without being too harsh. This light blue shade is soft both to the eye and touch. They instantly add a touch of whimsy and look amazing as textural elements in boutonnieres, corsages, and bouquets. They may be too small to make much impact in an average centerpiece, however, they work fine in bud vases.
