Some flowers will be available all year round which does make the decision easier.
Versatile and hardy, lavender can grow into thick hedges and be used to provide pops of colour to any floral arrangement. Also used as a flavour in cooking as well as regarded for its stunning purple colour, there's nothing lavender can't do. It's perfect as a centerpiece flower for more rustic, country weddings and perhaps necessary for any set in the South of France, but it can also be used to offset more formal roses in a bouquet. Here, it's beautifully represented in watercolour and used as a border in these wedding invitations.
If you can't make it to Provence, there are lavender farms all over which make idyllic wedding venues.