If you have dried flowers, you know how much dust they can accumulate over time. . To clean them, you can place them in a bag with salt and cornmeal. Gently shake the bag, then remove the flowers and dust them with a hairdryer. Apply a little hairspray to protect them.
Artificial Flowers-Dusting frequently with a hair dryer set on low prevents build up that can become hard to remove. (This can be applied to dried flowers as well) To clean safely, without using water, pour some salt into a plastic bag and shake. Place a nylon stocking over a vacuum nozzle and gently remove the salt which will have absorbed the dirt from the flowers
*******Consumer Reports "How To Clean Practically Anything"