I decorate with a lot of dried flower arrangements and sometimes I use silks with them. After time they become dusty and fragile. I then buy the cheapest bath tub cleaner at the dollar store (ex. scrubbing bubbles or anything that foams and that will stay on the arrangement).
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If you have silk flowers that have gotten a bit dusty, you can put them in a bag with a handful or two of cornmeal, and shake the closed bag around for a bit. When you remove the flowers, the dust will be gone.
Now some of you may get a real chuckle out of this, but believe me it works so well. I have a lot of silk flower swags and silk flower wreaths.
Clean your silk flowers and greenery with diluted Murphy's Oil Soap! I was cleaning some furniture this week with the diluted mixture in a spray bottle and saw a basket of silk greenery that was dusty and needed a good cleaning.
I discovered something a few months ago while doing the weekly cleaning. I love silk plants, but hate the dust they collect.
Refurbishing A Silk Flower Swag. I have an expensive silk flower swag that I had made for my bedroom almost 10 years ago. The greenery on it was looking pretty sad and had lots of dust on it.
Dust your silk or dried flowers arrangement with a blowdryer set on low. Best done outside.