Greenery is sometimes dull when coming from the farm in dry pack. I generally like to rinse off the stems of my greenery, because there is often dirt and mud still clinging to the bottom of the stems. This can introduce bacteria into water buckets shortening the life of the greens.
Washing with regular tap water can sometimes leave a splotchy white film after it dries. This is from the minerals found in hard water. Florists use a spray called "Leafshine" or other type of plant polish to spray onto the leaves and leave a nice, clean, glossy finish.
Do this BEFORE adding fresh flowers. They are sealed with a different kind of spray designed especial for porous petals.