Wrap your fresh flowers with a polyethylene plastic sheets and put them in a cartoon box but not overcrowd them. Arrange them properly in such a manner that they're comfortably placed.
Those in the vases, you place them too in a cartoon or foam box but put a cartoon or foam divider between each vase not to touch each. Place them fit in every box so that they'll stay fix in the box.
If you can travel in the evening or early morning the better when the temperature is cold, to lessen the stress of the flowers.
I hope this helps you.
Happy wedding!
Cris
www.crisramasasa.com