Hattie the Hen
Deeply Rooted
vfem
I thought that this link to one of my favourite UK blogs might interest you. She also sells bunches of flowers from her garden & has been exploring the possibilities of their presentation. There is also a handy tip in this article about putting the stems in very hot water so they stay fresh longer.
http://www.cottagesmallholder.com/how-to-make-a-temporary-vase-for-cut-flowers-6660
The book she talks about by Sarah Raven is a smasher & well worth a good look -- I don't know if you could get it at your library? I know you would just love it. It is full of mouthwatering photos of various colour combinations of flowers.
Hope it helps & your scheme goes well.
Good Luck!
:happy_flower Hattie :happy_flower