I think the product I used to dry some bridal flowers was called silica gel. And I wouldn't recommend using it with edible products, as I think it's the same stuff they put in little capsules and packets to keep pills and capsules dry; it's clearly labeled that it should not be ingested.
Thank you! Silca, that's what I was looking for. Is it safe to put in contact with food though? If they put it in with some medications like Mezz says, it should be safe to put it in with the flowers, right?
I have used silica to keep many types of foods dry. I kept a tray of it on the bottom of a cabinet rolling rack, and stored the cookies, etc. above it. Just make sure there's no chance of it coming into contact with your food. Although for professionals, I'm sure it's a health code violation.